He played in Major League Baseball (MLB) for 2 seasons with the San Francisco Giants and Cincinnati Reds.

In the summer of 2008, he returned to the CCBL to play for the Hyannis Mets, where he was named a league all-star, and made headlines by crushing three home runs in a single game, the first CCBL player to accomplish the feat since baseball hall of famer Frank Thomas did it twenty years earlier.

On February 11, 2015, Dominguez signed a minor league contract that included an invitation to spring training with the Cincinnati Reds.

[9] On December 15, 2015, Dominguez signed a minor league contract with the Boston Red Sox that included an invitation to spring training.

[10] He spent the entire 2016 season with the Triple-A Pawtucket Red Sox, playing in 77 games and hitting .241/.275/.439 with 13 home runs, 39 RBI, and 7 stolen bases.

[11] Dominguez signed a minor league contract with the Chicago Cubs organization on January 16, 2017, which included an invite to spring training.

[12] He spent the year with the Triple-A Iowa Cubs, playing in 102 games and hitting .284/.323/.443 with 11 home runs, 45 RBI, and 12 stolen bases.

He played in 84 games for the Triple–A Syracuse Chiefs, batting .243/.293/.406 with nine home runs, 45 RBI, and seven stolen bases.