LOS ANGELES — On April 11, in the seventh inning of a game against the New York Mets, the Phillies’ Bryce Harper made a throw from right field to home plate. He grabbed his right elbow immediately after the ball left his hand and winced, crouching down for a few seconds before brushing himself back up. He remained in the game, and underwent an MRI shortly after that showed he had a flexor strain. But as Harper continued to lightly throw over the next few weeks, he realized the pain wasn’t going away.

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So, the Phillies got a second test done, which revealed a different, more serious diagnosis: a small tear in Harper’s ulnar collateral ligament. On Thursday morning, the right fielder met with Los Angeles-based Orthopaedics Sports Medicine specialist Dr. Neal ElAttrache, who confirmed that Harper indeed had a small tear in his UCL.

Harper is scheduled to have a platelet-rich plasma (PRP) injection on Sunday. This will take him out of the Phillies’ lineup for Sunday’s game against the Dodgers, and potentially Tuesday’s home game against the Padres.

Phillies manager Joe Girardi said Harper will not throw for four weeks. The team hopes that he’ll be able to start a throwing program after that, but there is no firm timetable for him to start such a program, or to return to right field. Harper will continue to DH in the meantime. He has not played right field since April 16.

“I think I need to look at the positives of being able to DH,” Harper said. “If this were last year, or the past few years, I wouldn’t be able to do it. I can still be on the field, I can still help this team on this side of the ball. Of course, I want to be able to on that side of the ball, but I think the guys out there are going to take care of business.”

In more ways than one this is a situation that Harper — who recently accrued 10 years of service time — is unfamiliar with. Even dating back to his high school baseball career, he’s never experienced pain in his right elbow. He has also never received a PRP injection before, so he’s uncertain of how he might react to it. But the 2021 NL MVP is relieved that he finally has answers.

“Obviously I’m glad that I know and have some clarity on where it’s going to go from here,” Harper said on Thursday. “That’s about it. I’ll get the shot on Sunday, see how I feel the next couple weeks, and go from there.”

Eflin feeling better

Zach Eflin, who was placed on the COVID-related IL on May 8, is feeling better, according to Girardi. The Phillies hope — and expect — that Eflin will be able to make his start on Tuesday in Philadelphia against the Padres, which is why they optioned left-handed pitcher Bailey Falter back to triple-A Lehigh Valley on Thursday.

“We wanted to keep (Falter) going,” Girardi said. “If Eflin is able to make his start on Tuesday, which we believe he will be, we would waste four or five days with Bailey, because when you option him down he has to be down 15 days. We told him it’s nothing he did wrong, he did everything right, but we want to be able to build him up. Because at some point we’re going to need another starter and at some point, we have doubleheaders. He pitched really well (in his last outing.”

Update on Gregorius

Shortstop Didi Gregorius, who was placed on the 10-day IL with a left knee sprain on May 7, still has no time table for a return, according to Girardi.

“He’s out here doing more and more,” Girardi said on Thursday. “He’s getting stronger. He’s doing more in the weight room. I think he’s done swings in a chair. But don’t have an exact time frame on him yet.”