The Boston Red Sox may have caught another tough break with starting pitching health on Tuesday.

Last spring, new Red Sox acquisition Lucas Giolito had to leave his spring training start on Mar. 1 with elbow discomfort, and it turned out he would require internal brace surgery to repair his ulnar collateral ligament. That cost him his entire first season with the club.

After a painstaking year of rehab, Giolito was looking forward to a two-inning outing against the Philadelphia Phillies after three live at-bat sessions over the last two weeks. But things didn’t go according to plan.

After pitching just one inning in his first start of any kind since the surgery, Giolito had to cut his outing short. The Red Sox confirmed to reporters in attendance that Giolito left the game with left hamstring tightness.

As for the outing itself, Giolito allowed two earned runs on two walks, a double, and a pair of sacrifice flies. He faced six hitters, all of whom saw significant time on the Phillies’ major league roster last season.

According to Sean McAdam of MassLive, Giolito felt the hamstring tighten on the first pitch of his outing, but feels the issue is “very minor” compared to past strains.

At the time of publication, there was no word on whether Giolito’s spring training progression would be interrupted, but there’s certainly an increased chance that the righty could miss out on making his Red Sox debut during the team’s opening series against the Texas Rangers.

The Red Sox were already dealing with the expected absences of Kutter Crawford and Brayan Bello to begin the season, so Giolito’s injury would bring Boston down to just three healthy starters among those projected for rotation spots throughout the offseason.

Fortunately, 25-year-old Richard Fitts and 24-year-old Quinn Priester, both of whom have impressed with improved velocity throughout the spring, look prepared to step in on at least a temporary basis.

Any suggestion that Red Sox might employ a six-man starting rotation to begin the 2025 season now looks preposterous in hindsight. But this is why pitching depth is so important, and why the trades to acquire Fitts and Priester were wise decisions based on the team’s needs at the time.