Most baseball trades require years of data to determine a winner and a loser.
In the case of the December 2015 deal that sent right-hander Shelby Miller from the Atlanta Braves to the Arizona Diamondbacks, the only difference additional time will make is in deciding whether it was merely the worst trade of the year or one of the worst in a generation.
The swap was likely a big reason why Diamondbacks general manager Dave Stewart was fired on Monday.
To acquire Miller, who was coming off a 6-17 season, and minor league left-hander Gabe Speier, Arizona sent outfielder Ender Inciarte, right-hander Aaron Blair and minor league shortstop Dansby Swanson to Atlanta.
Inciarte developed into a Gold Glove candidate and hit .291 with three homers and 29 RBIs in 131 games for the Braves.
Swanson, the No. 1 overall pick in the 2015 draft, broke into the majors with the Braves in August and hit .302 with three homers and 17 RBIs in 38 games.
Miller, meanwhile, finished 3-12 with a 6.15 ERA and earned a midseason demotion to the minors during his fifth major league season.
Headlined by Miller, here is a look of each National League team's most disappointing player in 2016, as chosen by The Sports Xchange's national network of baseball writers.
RHP Shelby Miller was brought in to be the No. 2 starter, but he struggled so much that he was optioned to Triple-A Reno after the All-Star break to regain his bearings. Miller finished the season with 11 scoreless innings in his last two starts, so there's that. He wound up 3-12 with a 6.15 ERA in 20 starts. Miller gave up 127 hits in just 101 innings, and he walked 42 while striking out 70.
OF Gerardo Parra, who signed a three-year, $27.5 million free contract agent last winter, fell far short of his career norms this year. He hit .253/.271/.399 with seven homers and 39 RBIs in 102 games with just nine walks in 381 plate appearances. A high left ankle sprain caused him to miss 46 games, and upon returning, Parra, due to the rise of rookie OF David Dahl, became a fourth outfielder and occasional first baseman. Parra is expendable, but he is owed $19.5 million, including a $1.5 million buyout on a $12 million club option in 2019.
LOS ANGELES DODGERS
LHP Hyun-Jin Ryu was limited to one disastrous start this year because of injuries. Ryu missed the entire 2015 season after undergoing shoulder surgery but failed to bounce this year despite a season-long effort and rehab stints. On Sept. 28, he underwent yet another elbow procedure -- an arthroscopic debridement to remove damaged tissue -- and the Dodgers are optimistic he will return in 2017. However, they have been looking forward to his return for years.
SAN DIEGO PADRES
RHP Tyson Ross never pitched for the Padres again this year after sustaining a mysterious shoulder injury on Opening Day against the Los Angeles Dodgers. After winning a combined 23 games and averaging 196 innings with a 3.03 ERA over the previous two seasons, Ross was done after 5 1/3 innings this season. What was originally described as shoulder inflammation became a question mark. Offseason surgery is a possibility after three comeback attempts all failed.
SAN FRANCISCO GIANTS
Giants fans are ready to crucify RHP Santiago Casilla, but let's be realistic. The guy was promoted from setup man to closer, and he now is back being a setup man, which is where he belongs. And he did save 31 games, which isn't bad. On the other hand, you could argue that CF Denard Span didn't have 31 good games all season. The key offensive acquisition in the offseason inexplicably retained the leadoff spot most of the season despite stealing fewer bases in six months (12) than 3B Eduardo Nunez did in two (13).
OF Jason Heyward signed an eight-year, $184 million deal prior to 2016 and went on to a hot-and-cold regular season, batting .230 with seven homers and 49 RBIs and career-low slugging (.325) and on-base (.306) percentages. He managed just three homers in 75 home games and posted an anemic .305 slugging percentage at Wrigley Field. A lifetime .262 batter, he hit .293 for the St. Louis Cardinals in 2015. The lackluster offense was somewhat offset by Heyward's steady and occasionally spectacular defensive play.
RHP Homer Bailey came into spring training expecting to return to the rotation by late April or May. Following setbacks in his rehab from Tommy John surgery, Bailey didn't make his first start for the Reds until July 31. After posting a 6.65 ERA in six starts, Bailey was shelved again with biceps soreness. Bailey, who owns a pair of no-hitters in his career, signed a six-year, $105 million contract in 2014. He has made eight starts the past two seasons combined.
OF Domingo Santana was penciled in as the Opening Day starter in right field but never seemed to get comfortable and struggled to stay on the field. He appeared in just 77 games for Milwaukee, battling a series of arm and shoulder injuries, and he batted .256 with 11 home runs and 32 RBIs. The Brewers still have high hopes for Santana, so it is likely he will be on the roster come Opening Day, but with a glut of talent in the minor leagues, Milwaukee will have options if Santana can't get it together.
RHP Gerrit Cole, 26, was needed to be a solid member of the rotation, if not the No. 1 starter, after winning 19 games last year, but inconsistency and injuries held him back. He was 7-10 with a 3.88 ERA and a 2.72 strikeout-to-walk ratio. In his final five outings, he went 0-4 with an 8.37 ERA. Cole made just one start in September due to right elbow posterior inflammation that led to two stints on the disabled list.
ST. LOUIS CARDINALS
RHP Trevor Rosenthal came into the season as the team's lockdown closer and lost his job before the calendar hit July, the result of too many walks and too many blown saves. It turned out Rosenthal was pitching with shoulder pain, and he wound up on the disabled list. When he came back in September, albeit in a low-leverage role, he looked much better and gave St. Louis three key innings in a critical win Oct. 1 over Pittsburgh. He finished 2-4 with a 4.46 ERA but will figure into the late-inning mix next year.
RHP Matt Wisler began the season as the team's No. 2 starter but had his stock fall after an uneven 2016. He went 7-13 with a 5.00 ERA and 115 strikeouts in 156 2/3 innings. However, he allowed a team-worst 26 home runs -- four more than RHP Julio Teheran yielded even though Teheran threw 32 more innings. The Braves like Wisler's makeup and his approach, but he will have something to prove in spring training.
LHP Wei-Yin Chen, who signed a five-year, $80 million contract in January, was a flop in his first year with Miami. His contract is back-loaded, so if he continues to struggle, it will be impossible to trade him without virtually buying out the entire deal. Chen was a successful starting pitcher with the Baltimore Orioles, but with the Marlins, the soft-tosser went 5-5 with a 4.96 ERA in 2016. He must make some adjustments, as the Marlins badly need him to rebound next year.
NEW YORK METS
C Travis d'Arnaud collected 27 extra-base hits in just 239 at-bats in 2015. He had only 11 extra-base hits in 251 at-bats this year, during which he missed nearly two months due to a shoulder injury and eventually lost his job upon his return to career-long backup Rene Rivera. D'Arnaud also threw out just 22 percent of opposing basestealers. D'Arnaud has long been touted as one of the best catching prospects in the game. but he will be 28 by Opening Day 2017 and has been on the disabled list six times since 2012.
OF Aaron Altherr was limited to 57 games due a wrist injury and did not impress in his limited time. He is said to have gap power and some project him to be a 20-homer hitter. Instead, he had two home runs, batted .202 (40-for-198) and struck out 69 times in 57 games. While seeing everyday action as the right fielder after Sept. 1, Altherr batted .163 with no homers and four RBIs in 27 games.
Ryan Zimmerman, moved to first base after shoulder problems made throws from third problematic, was unable to put up the numbers he produced earlier in his career. In 115 games, he hit .218 with 18 doubles, 15 homers and 46 RBIs, and he posted a .192 average in his final 30 games. The word among pro scouts who follow the Nationals is that Zimmerman has trouble getting around on good fastballs. Zimmerman is signed through 2019, with a club option for 2020.