Marcus Markley Thames (pronounced "TIMMS") (born March 6, 1977 in Louisville, Mississippi) is an outfielder and first baseman in Major League Baseball who currently plays for the Detroit Tigers. He attended East Central Community College in Decatur, Mississippi, where he was known by friends and teammates as "Slick." He was drafted by the New York Yankees in the 30th Round of the 1996 amateur draft.

Thames warranted "prospect" status from the Yankees following a standout 2001 season for the AA affiliate Norwich Navigators, in which he batted .321 with 31 home runs and 97 runs batted in. For his efforts he was named to the Baseball America minor league all-star team.

On June 10, 2002, Thames began his major league career with a bang as he was the 80th player in history to hit a home run in his first at bat. Thames hit the home run off the first pitch he saw from Randy Johnson of the Arizona Diamondbacks. As his coaches and teammates were laughing in amazement, Thames stepped out of the dugout for a curtain call to a capacity crowd at Yankee Stadium.