A's Surging Starter Dealing with Forearm Tightness

Jacob Lopez had been cruising since his final start in July, holding a 0.60 ERA across 30 innings of work in five starts, but on Sunday against the Seattle Mariners, the A's rookie left-hander had his worst outing of the year.

In two plus innings of work, Lopez allowed six hits and a career-high six walks, which led to nine earned runs. He also struck out two and gave up Cal Raleigh's 48th and 49th home runs on the year.

After the game, A's manager Mark Kotsay told reporters that Lopez had been diagnosed with left forearm tightness, which he'd been feeling a little since his previous start in Minnesota. Lopez will be looked at on Monday when the team is back in West Sacramento, but for right now his status is very much uncertain.

Depending on the type of injury and what the remedy is for said injury, the A's may have to add more starting depth than they'd been planning on this offseason. Just a week ago, Lopez had been cruising and Jack Perkins was showing that he could be a legitimate starter in the big leagues. Perkins is on the IL now, and there is a chance that Lopez will be joining him.

The A's rotation right now only has one member that is certain to be in the rotation to start 2026, and that is Jeffrey Springs. Luis Severino is also on the IL at the moment, and if all three of Sevvy, Perkins and Lopez are healthy, they would presumably fill 60% of the A's rotation. This is of course with the current members of the roster, though some moves could be made this offseason.

The A's will also have young up-and-comers like Luis Morales (currently in the rotation) vying for a spot, while Mason Barnett and Kade Morris could serve as depth options, at least initially.

They also have 2024 draftee Gage Jump that could be ready in the first couple of months of the '26 campaign, while 2025 draftee Jamie Arnold serves as a wild card. He could move quickly, but that will be determined by how well he performs after making his pro ball debut.

In addition to those names, there's also Osvaldo Bido, Joey Estes, J.T. Ginn, Gunnar Hoglund and Mitch Spence, most of whom have spent time with the A's this season both in the rotation and in the bullpen.

So there are even guys with big-league experience with the club that could be ready to slot into a rotation spot next year, but the big question will be whether the A's are looking to make a big upgrade on the pitching market. Even without the injuries, you'd have to think they'd be looking to bring in an arm or two as potential rotation options.

Finally, the A's also have left-hander Ken Waldichuk and righty Luis Medina, both of whom have been out for the year while they're recovering from Tommy John surgery. Waldichuk is currently rehabbing in the minors, and his velocity hasn't quite returned to where it was before his injury. The hope is that with a full offseason of work that he'll be where he was in 2023.

Medina is an interesting case, because he'll be out of options, and the A's could also use some bullpen depth. It's possible that they look at that situation and decide to make him a relief picher, with the thought being that he could pitch later innings as the season progresses.

That would also allow the A's to work him into the season more gradually, instead of needing him to be ready to throw at least five innings by Opening Day.

While the A's have plenty of pitching options available to them, if they were to lose Lopez for an extended period, that could change their plans heading into the offseason. The rookie left-hander has shown this season what he's capable of, and the hope would be to have him build upon that next season, perhaps even turning into a top one or two pitcher in the A's rotation.

W'll have to wait for an update on his status on Monday afternoon.