Thomas Andrew Pomeranz (born November 22, 1988), nicknamed Big Smooth, is an American professional baseball pitcher in the Seattle Mariners organization.

[9] On July 31, 2011, Pomeranz, Alex White, Joe Gardner, and Matt McBride were traded to the Colorado Rockies for Ubaldo Jiménez.

[10] He made his Major League debut when he started and pitched five scoreless innings to pick up the win against the Cincinnati Reds on September 11.

[14][15] Pomeranz began 2014 as a member of the A's bullpen, where he made 9 appearances, going 1–1 with a 1.98 ERA in 13.2 innings, before being moved to the rotation on May 9 to replace the struggling Dan Straily.

Despite raising his ERA a full run higher from the previous season, Pomeranz finished appearing in a career-high 53 games, recording 3 saves and logging in 86 innings.

On December 2, 2015, the Athletics traded Pomeranz, José Torres, and a player to be named later or cash considerations to the San Diego Padres for Marc Rzepczynski and Yonder Alonso.

Pomeranz made the Padres' starting rotation, and was named to appear in the 2016 MLB All-Star Game after posting a 2.47 ERA and leading the NL with a .184 batting average against in the first half.

[23] During the 2016 MLB All-Star break, the Padres traded Pomeranz to the Boston Red Sox for Anderson Espinoza, a highly regarded minor league pitching prospect.

[24] On September 16, 2016, Padres general manager A. J. Preller was suspended for 30 days for keeping two sets of medical records for players—one internal and one for league use.

For the 2017 Red Sox, Pomeranz had a record of 17–6 with a 3.32 ERA in 32 appearances (all starts), registering 174 strikeouts and 69 walks in 173+2⁄3 regular season innings.

[28] In the postseason, he started Game 2 of the ALDS against the Houston Astros; he only pitched into the third inning while allowing four runs (18.00 ERA) and took the loss.

On June 5, he was placed on the disabled list due to left biceps tendinitis;[31] he was activated on July 24 as a relief pitcher.

Pomeranz was initially not included on Boston's postseason roster,[33] but was added for the World Series in place of Brandon Workman.

[43] He did not appear in a game for San Diego in 2022, and began the 2023 season on the injured list as he recovered from left elbow flexor tendon surgery.

[51] In eight games for the Triple–A Oklahoma City Baseball Club, he posted a 6.00 ERA with 14 strikeouts across nine innings of work before he was released by the organization on May 23.