Trevor McDonald allows three runs in no-decision

After undergoing Tommy John surgery McDonald will miss the rest of this season and likely most of 2027. This is a procedural move to free up a roster spot for waiver-claimed 3B Shay Whitcomb.

It’ll be a full ligament replacement procedure with Dr. Keith Meister for McDonald after being diagnosed with a UCL sprain earlier this month. Given the timing of the procedure, he’s likely to miss most, if not all, of next season as well.

The Giants want to make sure that the ligament damage isn’t more significant before deciding on the best recovery plan for the 25-year-old right-hander. He remains without a timeline for his potential return and fantasy managers in redraft leagues are probably safe to cut bait at this stage.

McDonald hits the shelf after making an early exit from Monday’s start against the Royals after just four innings due to elbow discomfort. The 25-year-old, who holds a pedestrian 5.12 ERA across 70 1/3 innings over 14 starts this season, will undergo additional imaging to determine the severity of the issue and there should be a definitive return timeline in the coming days. He was slated to face the Angels on Sunday. No word how the Giants will fill his rotation spot.

The one run came on Jake McCarthy’s inside-the-park homer to open the game. The Giants didn’t take the lead until the bottom of the eighth, so McDonald went unrewarded for his fine effort. He ends the first half 3-7 with a 5.02 ERA and a 54/21 K/BB in 66 1/3 innings over 13 starts. There isn’t much fantasy upside here, but with his groundball ability, he should do well enough to stick in the San Francisco rotation the rest of the way.

After a scoreless first inning, McDonald surrendered a three-run homer to Jonathan Clase in the second. Five hits in the third inning would bring five more runs across and chase McDonald from the game with two outs at 58 pitches. He failed to record a strikeout. The 25-year-old right-hander ends the day with a 5.31 ERA, 1.38 WHIP, and a 50/20 K/BB ratio across 59 1/3 innings.

He struck out five. McDonald’s first scoreless start as a big leaguer comes after six straight losses and moved him to 3-6 with a 4.42 ERA through 11 starts this season. His strong groundball rate bodes pretty well going forward, but he’s still going to need to produce more strikeouts with his slider in order to turn into more than a bottom-of-the-rotation guy. He’ll face the Blue Jays next week.

McDonald allowed an unearned run to score in the first on a bases-loaded walk following a fielding error. More defensive troubles put a second unearned run on the board for Miami in the second inning. After a scoreless third, he loaded the bases with no outs to start the fourth before he was pulled at 69 pitches. All three inherited runners would come in to score. Confirmed that he’ll remain in the rotation, the 25-year-old right-hander will take a 4.73 ERA, 1.34 WHIP, and a 42/18 K/BB ratio across 45 2/3 innings into a start against the Braves in San Francisco on Friday.

Houser has really struggled through his first 14 starts on the season, posting a 5.73 ERA, 1.58 WHIP and a 48/25 K/BB ratio over 66 innings. Any fringe fantasy value that he may have had in deeper mixed leagues or NL-only formats evaporates on this news. That means that Trevor McDonald will remain in the Giants’ rotation going forward.

Mahle threw just 33 of his 63 pitches for strikes and got three whiffs on 20 swings. His velocity was fine, sitting 93.2 mph on his four-seamer, which is better than we saw in recent MLB starts. However, given how inefficient he was, it would be shocking if the Giants brought him back later this week. We’d expect him to make at least one more start at Triple-A, which should allow Trevor McDonald to take another turn in the rotation.