Sandoval (elbow) did not make his scheduled rehab start for Double-A Portland on Sunday, because the game was postponed due to weather, Christopher Smith of MassLive.com reports. The left-hander will now start Wednesday for Triple-A Worcester.

Sandoval is returning from an internal brace procedure that he underwent in 2024 and prevented him from pitching in 2025. The Red Sox will eventually need to decide on a role for Sandoval. Connolly Early is currently the fifth member of the team's rotation, and it's possible that Sandoval works as a long reliever.

Montero (0-1) took the loss Sunday against the Cardinals, allowing three runs (two earned) on three hits and one walk while striking out three over 4.1 innings.

Making his first start of the season in place of Justin Verlander (hip), Montero was sharp early, retiring 12 of the first 13 batters he faced and holding St. Louis scoreless through four innings. The right-hander ran into trouble in the fifth however, allowing three baserunners, including an RBI single from Pedro Pages that ended his outing. Both inherited runners eventually came around to score, accounting for his final line. Sunday's strong start was an encouraging sign for Montero after he posted a 4.37 ERA and 1.39 WHIP with 72 strikeouts across 90.2 innings in 2025 and he'll look to build on the early success in his next outing against a Miami lineup that has started the season swinging well.

Pfaadt did not factor into the decision Sunday against Atlanta, allowing three runs on six hits and two walks while striking out two over 4.2 innings.

Pfaadt got off to a shaky start, surrendering a solo homer to Drake Baldwin just two batters into the game, but he briefly settled in by retiring 10 of the next 13 hitters. The right-hander ran into more trouble in the fifth inning, where two more runs came across, including one on a wild changeup that reached the backstop, allowing a free runner to come home. After surrendering five runs in his season debut and a disappointing Sunday, it's been a slow start to 2026 for the 27-year-old. Pfaadt will look to bounce back in his next outing against Philadelphia, a lineup that has been roughly middle of the pack offensively to begin the season.

Perez did not factor into the decision Sunday against the Diamondbacks, allowing four runs on five hits and one walk while striking out one over five innings.

After opening the year with 4.1 scoreless innings out of the bullpen, Perez failed to find much consistency in his first start of the season. The 35-year-old ran into trouble right away, allowing a leadoff double to Ketel Marte, who later scored on a sacrifice fly. Perez continued to pitch from behind throughout the outing. The biggest damage came in the fourth inning, when Ildemaro Vargas lined a two-run triple down the right field line, handing Arizona the lead. Despite throwing 75 pitches (47 strikes), Perez generated little swing-and-miss (four whiffs) and finished with just one strikeout on the day.

Klassen didn't factor into the decision, allowing two runs on three hits and five walks while striking out four over 2.2 innings Sunday against the Mariners.

Making the start on short notice, Klassen's debut was a mixed bag, with him flashing electric stuff but struggling with command and exiting early. The 24-year-old picked up his first career strikeout in a big spot, fanning Julio Rodriguez with a runner on third to escape the first inning. However, Seattle's patience forced him into a long second inning, where he allowed a two-run single before limiting further damage with another punchout. The right-hander's outing ended in the third after a bunt single and wild pitch put another runner in scoring position. Klassen's fastball (97-98 mph) and hard slider (92 mph) highlight his upside, but sharper control will be necessary for him to stick in a starting role anytime soon.

Webb didn't factor into the decision Sunday against the Mets, allowing one run on seven hits and one walk with three strikeouts across seven innings.

Webb's only blemish was an RBI single allowed to Mark Vientos in the second inning. Webb scattered the seven hits but had a 2-1 lead when he left the game following the seventh inning. Keaton Winn and Erik Miller combined to allow four runs on five hits in the eighth inning to blow Webb's potential win. Webb will take his fourth turn through the rotation Saturday on the road against the Orioles. He has a 5.00 ERA and 15:6 K:BB across 18 innings.

Castillo did not factor into the decision Sunday against the Angels, allowing four runs (three earned) on six hits and one walk while striking out four over 3.2 innings.

Castillo couldn't find a rhythm in this one, allowing at least two baserunners in every inning he worked and exiting before completing four frames for the first time since 2024. The right-hander ran into trouble immediately, allowing a leadoff double to Zach Neto before Jorge Soler brought him home with an RBI single, and the outing didn't improve much from there. Unlike his dominant Opening Day outing in which he tossed six scoreless innings with seven strikeouts, Castillo failed to fool hitters Sunday and was consistently pitching under pressure. The 33-year-old will look to bounce back in his next scheduled start against Houston, though it presents a tough test against one of the league's most productive offenses early in 2026.

Senga (0-1) didn't factor into the decision Sunday against the Giants, allowing two runs on five hits and two walks with seven strikeouts across 5.2 innings.

Senga was flawless through five innings, allowing two hits and two walks, and held a 1-0 lead going into the bottom of the sixth. The wheels then fell off a bit for the right-hander, as he surrendered two runs on three hits before being pulled in favor of Huascar Brazoban. Senga's stuff again looked good Sunday, and he now owns a 3.09 ERA and 16:5 K:BB across 11.2 innings. Senga is slated to take the mound for his third start Saturday at home against the Athletics.

McCullers (1-0) didn't factor into the decision Sunday against the Athletics, allowing three runs on five hits and three walks with four strikeouts across four innings.

McCullers opened the game with four scoreless innings but allowed the first three batters to reach base to begin the fifth and was yanked in favor of Steven Okert, who allowed his two inherited runners to score on a bases-loaded triple by Tyler Soderstrom. McCullers will bring a 3.27 ERA and 13:4 K:BB across 11 innings into his next start Saturday on the road against the Mariners.

Quintana (hamstring) has resumed playing catch, MLB.com reports.

Quintana returned to throwing only three days after being placed on the injured list, a positive sign that his absence won't be long-term. However, he also hasn't been cleared for any additional activity, so his exact timeline for a return is unclear.