BOSTON — Red Sox starter Drew Pomeranz has walked off the mound before the start of fourth inning with left triceps tightness in Sunday's game against the Tampa Bay Rays.
The team announced the injury in the fifth inning.
Pitching in chilly conditions with light drizzle falling most of the game, the left-hander finished his warm-up pitches and rotated his arm before manager John Farrell and a trainer jogged to the mound.