ANAHEIM -- Rookie right-hander George Klassen had been on a solid run since joining the rotation in early August, but he was placed on the 15-day injured list with left lower back inflammation before Sunday's 5-2 loss in the series finale against the Phillies.
The move was retroactive to Thursday, which was the day that Klassen started to feel the symptoms -- three days after he allowed two earned runs over 5 1/3 innings against the Guardians. But Klassen, ranked as the club’s No. 12 prospect by MLB Pipeline, said he’s still able to play catch and is optimistic it’s just a minor injury.
“It’s getting better,” Klassen said. “Just need a little rest, I think. It’s a long season, we're getting to the back end of it. So in just a couple of days, we'll be all right.”
Klassen, 24, has gone 2-2 with a 3.67 ERA, 24 strikeouts and 21 walks in 27 innings across six starts this season. But after struggling in his first two outings in early April, he had an impressive stint at Triple-A Salt Lake to earn his spot back in the rotation on Aug. 7. Since then, in four starts he's posted a 2.01 ERA with 18 strikeouts and 11 walks in 22 1/3 innings.
“A lot of positives to take from every day and days in between,” Klassen said. “Just keep building off things and stacking them.”
With Klassen out until at least Sept. 11, the Angels will revert to a five-man rotation, as lefty relievers Mitch Farris and Blake Weiman were both brought up from Triple-A Salt Lake, with right-hander Trevor Martin optioned.
The Angels were previously using a six-man rotation with the return of lefty Yusei Kikuchi, who started Sunday against Philadelphia. He rejoined the rotation on Aug. 23 after missing roughly four months with left shoulder inflammation, and had a strong showing against the Phillies, allowing two runs on six hits over seven innings.
Angels manager Kurt Suzuki said they don’t anticipate Klassen to be out too long, as they don’t believe it’s a season-ending injury. Klassen is at 118 combined innings between Triple-A and the Majors this year after throwing 108 2/3 innings in the Minors last year, so he’s also not making a huge jump in innings.
“He felt it a little bit, and obviously, just out of precaution,” Suzuki said. “Just want to make sure that we can get it before it turns into something big. But he's not concerned. I'm not concerned, either. It's just to stay ahead of it.”
Suzuki, though, has been impressed with Klassen, who is one of several rookies to step up in the rotation, along with the emergence of right-handers Walbert Ureña and Ryan Johnson. Since the beginning of August, Angels starters have combined to post a 2.57 ERA, which ranks as the best mark in the Majors.
“He's been great,” Suzuki said of Klassen. “He's been making huge strides, and I think the consistency has been getting better and better every time he gets out. You can kind of see the comfort level within every start, right?”
Klassen was slated to face the Yankees on Monday, but Ureña will now make that start. He’ll be followed by right-hander Grayson Rodriguez on Tuesday and lefty Reid Detmers on Wednesday.