Suspensions for alleged banned substance use, a bombing at the end of the one of the most prestigious marathons and long-term issues from sports injuries top the year in sports.
There were moments in competition important to more than just 2013 such as Jamaicans Usain Bolt and Shelly-Ann Fraser-Pryce dominating the sprints at the world track and field championships and Andy Murray becoming the first British man to win at Wimbledon since 1936.
There were melancholy occasions such as the retirement of baseball's relief specialist Mariano Rivera and of perseverance in Diana Nyad, at age 64, completing the 103-mile swim from Cuba to Florida.
There was the astounding last-second return by Auburn's Chris Davis of a missed field goal that beat two-time defending college football champion Alabama and the heart-warming weaving run of 7-year-old Jack Hoffman through the Nebraska football team to score a touchdown, a sign of sports providing more than entertainment.
Two bombs were detonated near the finish line of the Boston Marathon, killing three people and injuring more than 200 others. More than a dozen of the injured had to have limbs amputated. Two brothers -- one who was killed during a manhunt and the other who awaits trial -- were suspected of carrying out the attack.
However, the issues with the most impact on sports occurred off the field and continue in the courtroom: Investigations -- and lawsuits -- are piling up regarding lifelong problems caused by football-related brain injuries. Major League Baseball suspended 13 players -- some of them very high-profile -- suspected of using performance-enhancing drugs provided by Biogenesis of America, a "rejuvenation" clinic in Florida.
Most of the players, including 2011 NL Most Valuable Player Ryan Braun of the Milwaukee Brewers, were given 50-game suspensions and immediately began serving them. One, however, did not.
New York Yankees third baseman Alex Rodriguez, recipient of the two richest contracts in baseball history and a three-time selection as AL MVP, was slapped with a 211-game suspension. Rather than sit out, Rodriguez appealed the decision and played the rest of the season. His appeal process continued into late November and a decision isn't expected until 2014.
Former players, or their survivors, are fighting the NFL and demand action regarding the long-term effects of continued blows to the head in games and practices. Dozens of lawsuits allege those hits have led to life-altering issues such as chronic traumatic encephalopathy, a progressively degenerative disease affecting the brain and manifesting itself as dementia.
"League of Denial: The NFL, Concussions and the Battle for the Truth," by Mark Fainaru-Wada and Steve Fainaru and released in the fall, claims the NFL tried to discredit scientists and doctors and cited flawed research regarding brain-related injury issues.
The NFL and other sports organizations, notably the NHL, have instituted concussion-related protocols limiting players' return to the field, court or rink until they can pass a series of tests to indicate concussive effects have eased.
The spotlight on head injuries in the NFL is suspected to have played a role in the drop in participation in youth football programs, a study released in November indicated.
Another in years of denial was cyclist Lance Armstrong, who, in a January interview with Oprah Winfrey, admitted to PED use during his rides to seven consecutive Tour de France titles, championships since revoked.
Armstrong was named in a series of lawsuits, one by a former teammate -- Floyd Landis, who had his 2006 Tour de France championship stripped due to use of banned substances -- and others by insurance companies claiming fraud. The U.S. government entered the Armstrong legal fray, saying Armstrong should pay more than $100 million because Armstrong was in breach of contract with the U.S. Postal Service, which sponsored his cycling team, because of the drug use.
Organizers in Russia and Brazil continued their years-long preparations for two prime events of 2014 -- the XXII Olympic Winter Games in Sochi and the FIFA World Cup in South America.
Russia's human rights record and a law passed last summer in Moscow led to fears lesbian, gay, bisexual and transgender participants in -- or spectators at -- the Games could be subject to prosecution if they speak on behalf of homosexual rights. Russian officials assured the International Olympic Committee that won't be the case.
Activists complained the Sochi Games, centered in the city on the Black Sea and near the Caucasus Mountains, would be harmful to the environment and the geologic aspects of the area could be hazardous. In December, Russian authorities warned landslides in the Caucasus Mountains that could damage infrastructure important to the Games.
In Brazil, where the 2014 World Cup is a prelude to the 2016 Summer Olympics, a section of a stadium being erected for the World Cup collapsed in November, killing two workers. Brazilian officials said six stadiums -- half of those needed for the World Cup -- won't meet a Dec. 31 deadline for readiness.
Among other issues for World Cup officials is security. Authorities have promised to make the event "one of the most protected sports events in history" and showed their resolve by establishing a huge security zone ahead of the World Cup draw Dec. 6.
Violence is feared from a Brazilian populace concerned about the millions being spent on the World Cup and Olympics rather than aid for the poor. More than $900 million has been set aside for World Cup security measures alone.
On the field perhaps the most shocking development was Davis returning a missed 57-yard field goal attempt by Alabama. Davis took the kick deep in his own end zone, immediately picked up blockers and headed to the left sideline. His sprint didn't end until his own teammates caught up to him in the opposite end zone, giving Auburn a 34-28 win.
That electrifying run was directly responsible for Auburn earning a spot in the Bowl Championship Series title game against unbeaten Florida State. The Seminoles' season was keyed by freshman quarterback Jameis Winston, who won the Heisman Trophy, signifying the country's best college football player for the year, in a landslide vote.
One of the most improbable feats was Oracle Team USA's defense of the America's Cup in San Francisco Bay. Emirates Team New Zealand sailed out to a seemingly insurmountable advantage but Oracle Team USA won the final eight races to retain the oldest trophy in international sports. The New Zealand team won the first six races and was ahead 8-1, needing one win in the next eight races to lock up the regatta, before Oracle Team USA put together its streak. It kept the cup with a 44-second win on Sept. 25.
Boston, rallying to the "Boston Strong" slogan, met St. Louis in the World Series for a battle between the teams that tied for the best record in the major leagues. Boston won the final three games in closing out the series in six games. Ortiz was voted the series MVP, hitting .686 with two home runs and six runs batted in. After the Cardinals walked Ortiz four times in Game 6, he'd reached base in 19-of-25 World Series plate appearances.
The Baltimore Ravens defeated the San Francisco 49ers 34-31 in Super Bowl XLVII last February in New Orleans. Quarterback Joe Flacco was voted game MVP after a 22-of-33 passing performance for 287 yards and three touchdowns.
The game was also noted for a 34-minute delay when a power outage partially darkened the Superdome.
Rivera retired after 19 years in the major leagues -- all with the New York Yankees. He was 82-60 lifetime with a record 652 saves and 2.21 earned run average. He missed most of the 2012 season because of a knee injury but returned and posted a 6-2 record with 44 saves and 2.11 ERA. He was 8-1 with 42 saves in 96 post-season games. Rivera was selected to the All-Star Game 13 times and was on five World Series-winning teams.
In men's tennis, Rafael Nadal returned from an injury, won two -- French Open and U.S. Open -- of the four tennis Grand Slam events and regained the world No. 1 ranking. Nadal entered 17 tournaments in 2013, winning 10, finishing second in four and reaching the semifinals in two of the three others.
Serena Williams lost only four matches on the year in women's tennis. She won two major tournaments -- the French Open and U.S. Open -- and had nine other titles while reaching the No. 1 ranking for a sixth time.
Marion Bartoli won the Wimbledon women's title -- her first major championship -- and about a month later said her body "couldn't take it" and retired from competitive tennis.
Nyad had tried four times (in 35 years) to make the swim from Cuba to the United States without a shark cage. She accomplished the feat Sept. 2, saying, "We should never, ever give up ... you [are] never too old to chase your dreams."
The Auburn-Florida State BCS title game in January will be the final one under the current controversial system to try to determine a major-college football champion. BCS Executive Director Bill Hancock in April announced the "College Football Playoff," in which four teams will be chosen to decide a major-college football titlist with the first such championship to be decided Jan. 12, 2015.
The four teams are to be chosen by a committee of 15, headed by Arkansas Athletic Director Jeff Long. The committee includes former players and coaches but also former U.S. Secretary of State Condoleezza Rice, who is the only woman on the panel.
Rice, an avid football fan who said NFL commissioner would be her "dream job," made sports news in 2012 when she and Darla Moore were extended invitations to be the first female members at Augusta Country Club, home of the Masters golf tournament.
Bolt and Fraser-Pryce were selected the IAAF athletes of the year after they swept the sprint events at the track and field world championships. They both won the 100-meter and 200-meter races and were part of winning 4x100-meter relay teams.
Bolt has won eight world championship gold medals, the most for any athlete all-time.
In basketball, the Miami Heat repeated as NBA champions, beating the San Antonio Spurs 4-3 in the best-of-seven finals LeBron James was the finals MVP after scoring 37 points and getting 12 rebounds in a 95-88 Game 7 win.
Louisville collected its third NCAA men's tournament title by beating Michigan 82-76 in the final. Connecticut defeated Louisville 93-60 for the NCAA Division I women's title. It was the record-tying eighth national title for the Connecticut women.
The NHL ended a 119-day labor dispute and began an abbreviated season Jan. 19, with teams scheduled for 48 games rather than the usual 82. The Chicago Blackhawks won the Presidents' Trophy for having the best record and went on to defeat the Boston Bruins in the Stanley Cup finals.
In golf, Adam Scott won the Masters while Justin Rose took the U.S. Open and Phil Mickelson claimed the British Open before Jason Dufner won the PGA Championship. Scott, Rose and Dufner were all first-time major tournament winners. Henrik Stenson won the FedEx Cup and the European Tour's Race to Dubai, the first to win both in the same year. Tiger Woods won five times on the PGA Tour, was selected the tour's player of the year for an 11th time and ended the year ranked No. 1.
While men's golf had four different winners in major tournaments, women's golf had one player take three majors. Inbee Park claimed the Kraft Nabisco Championship, LPGA Championship and U.S. Women's Open. Stacy Lewis won the Women's British Open and Suzann Pettersen took the Evian Championship in the first year of five major tournaments for women's golf.
Sebastian Vettel collected his fourth consecutive Formula 1 drivers' title. Vettel won the last nine Grand Prix races of the season and 13 overall in 2013. Jimmy Johnson won his sixth Sprint Cup driving championship but first since he won five in a row from 2006-10. He won six races, including the season-opening Daytona 500, on the year. Scott Dixon won his third IndyCar title, winning four races over the season.
Deaths of notable sports figures on 2013 included:
Owner of the Houston Oilers/Tennessee Titans Bud Adams at age 90; motorcycle racer Andrea Antronelli at age 25; golfer Miller Barber at age 82; baseball umpire Wally Bell at age 48; basketball Hall of Fame member Walt Bellamy at age 74; former NHL player Shawn Burr at age 47; Pro Football Hall of Fame member Jack Butler at age 85;
Los Angeles Lakers owner Jerry Buss at age 80; former NFL player and sports commentator Todd Christensen at age 57; basketball coach Jack Curran at age 82; UFC fighter Shane del Rosario at age 30; Pro Football Hall of Fame member Art Donovan at age 89; tennis player and ATP Executive Director Brad Drewett at age 54; race car driver Sean Edwards at age 26; Pro Football Hall of Fame executive Pete Elliott at age 86;
Former NFL player Allan Ellis at age 62; former football coach Chuck Fairbanks at age 79; College Baseball Hall of Fame Coach Ron Fraser at age 79; former NFL player L.C. Greenwood at age 67; world champion boxer Emile Griffith at age 75; former NFL player Harlon Hill at age 80; former NFL player Thomas Howard at age 30; College Football Hall of Fame Coach Don James at age 80;
Pro Football Hall of Fame member Deacon Jones at age 74; College Football Hall of Fame member Doug Kenna at age 88; Basketball Hall of Fame member Bob Kurland at age 88; professional baseball player Sophie Kurys at age 87; race car driver Jason Leffler at age 37; tennis Hall of Fame member Gene Mako at age 97; Pro Football Hall of Fame member Mike McCormack at age 83; Former NBA player Joe Meriweather at age 59;
Olympic gold medalist and track star Pietro Mennea at age 60; deep-water diver Nicholas Mevoli at age 32; snowmobile racer Caleb Moore at age 25; world boxing champion Tommy Morrison at age 44; former NFL player Chuck Muncie at age 60; Baseball Hall of Fame member Stan Musial at age 92; world boxing champion Ken Norton Sr. at age 70; former NFL player Paul Oliver at age 29;
Baseball player Andy Pafko at age 92; College Football Hall of Fame member Jack Pardee at age 76; Football Hall of Fame member Clarence "Ace" Parker at age 101; NFL Coach Bum Phillips at age 90; former NFL player George Sauer at age 69; former baseball player George Scott at age 69; Basketball Hall of Fame member as a player and a coach Bill Sharman at age 87; race car driver Allan Simonsen at age 34;
Olympic sailing gold medalist Andrew Simpson at age 37; Former NFL player and broadcaster Pat Summerall at age 82; former NASCAR driver Dick Trickle at age 71; former NFL player Frank Tripucka at age 85; golf Hall of Fame member Ken Venturi at age 82; Baseball Hall of Fame Manager Earl Weaver at age 82; NBA referee Greg Willard at age 54.