Harvard-Westlake pitcher Lucas Giolito sidelined by elbow injury

Senior Lucas Giolito of Studio City Harvard-Westlake, arguably the No. 1 high school pitching prospect in the nation, sprained the ulnar collateral ligament in his right elbow in the seventh inning on Tuesday and will be sidelined for six to 10 weeks, Coach Matt LaCour said Wednesday.

“He’s probably done for our season,” LaCour said.

Giolito pulled himself with one out in the seventh inning of a game against Mission Hills Alemany after “he felt a grab on his last pitch,” his father, Rick, said.

LaCour told a reporter at the time that Giolito had injured his groin, but on Wednesday, he said he was trying to protect Giolito until information could be determined about the extent of his elbow injury.

“It’s not torn up to where he needs surgery,” LaCour said.

Giolito, a 6-foot-6 right-hander, has signed with UCLA. He was clocked last week throwing two pitches at 100 mph. He had an MRI exam on Wednesday.

“He’s crushed. His teammates are crushed,” LaCour said. “His coaches are crushed, and we’re going to have to spend the next two days getting back on track.”

The injury jeopardizes his status as one of the top picks in the June draft, according to one area scout. But much will depend on how Giolito responds to rehabilitation and what he is seeking as a signing bonus to pass up college.

eric.sondheimer@latimes.com

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