Phillies’ Bryce Harper (thumb) out indefinitely after being hit by pitch in San Diego

SAN DIEGO — The Phillies’ Bryce Harper has been diagnosed with a left thumb fracture after getting hit on the hand by a 97 mph pitch from Padres starter Blake Snell in the fourth inning of a 4-2 victory on Saturday. He is out indefinitely. He’ll undergo further evaluation over the coming days.

After he was hit, Harper fell to the ground. He hunched over in pain. Initially, he thought he had broken his hand or finger, but an X-ray revealed a fracture. He appeared to exchange some heated words with Snell while walking off the field, but said that the two players texted after the game to clear the air.

“I’ve been playing against Blake since we were 10 or 11 years old,” Harper said. “I know there was no ill will behind that at all. It’s part of the game. The inside pitch is part of the game. It just got away from him.”

Phillies president of baseball operations Dave Dombrowski said Harper is “definitely” going on the injured list. Harper said that he will see a doctor who specializes in thumb injuries when he is back in Philadelphia. He will see a second specialist if he needs to. Dombrowski said it’s too early to say whether it will require surgery.

Harper was in the midst of what seemed to be another MVP-caliber season. Entering Saturday’s game, the DH ranked second in the National League in OPS (.986) and slugging percentage (.602). He was third in the NL in extra base hits (37) and total bases (145) and fourth in batting average (.320).

It was a frustrating development not just because of how Harper was playing, but also because of the amount of injuries he’s had to deal with of late. Aside from the small tear in the UCL of his right elbow, that moved Harper to DH, he missed a few games with an infected blister on his left index finger. Now, he is going to miss more time, with yet another freak injury.

“I want to play,” Harper said after the game. “I want to be with the boys. I want to be out there each night playing, being out there for the boys, and staff, and everybody, the team, the organization. I hate being hurt. Things happen for a reason right? Everybody says that, but this reason sucks right now. At the same time, it is what it is. I’ve got to be positive for the guys in here. They’ll pick up the slack. I’m just really bummed for the organization, the guys, and the city of Philadelphia and the fans as well. I love running out there playing every day. It is what it is right now. But I’m definitely bummed.”

Dombrowski acknowledged it will be impossible to replace Harper, but the Phillies are going to try to move forward.

“That’s what teams have to do,” he said. “They have to pick up, even for their star players. You just have to do that. He’s a guy that’s really not replaceable on an individual basis, but we have to be in a position where other people have to step up offensively. We’ll make a move to try to get somebody here for [Sunday]. It’ll free up the DH spot for a couple of guys to rotate in, however Topper [Phillies interim manager Rob Thomson] decides to use those.

“But yeah, you never replace a guy like that. But the Braves won a World Series last year without [Ronald] Acuña. So, you just have to do that. You lose good players. Again, I don’t know how long he’ll be out at this point. I’m hopeful he’ll be back at some point. We just need to carry on from here on. We’ve still got a lot of good hitters in the lineup.”

No player will be looked to step up more than Nick Castellanos. The right fielder, who came to Philadelphia to provide a middle-of-the-order power bat, has not provided much power of late. After Saturday’s game, he is batting .071 over his last seven games.

“We’re all going to have to step up — me definitely included — to carry the weight we’re going to be missing,” Castellanos said. “It’s got to be done.”

“I think that we are where we are and we’ve won the games that we have,” he added. “And I still think that there’s a better version of Rhys, I think there’s a better version of JT, and there’s a way better version of myself. I think it’s only a matter of time until all of those show up and if they show up at the same time, baseball can get real funny.”

Dombrowski said he visited with Harper after he exited the game. He described Harper as “very emotional.”

“He’s had bad luck,” Dombrowski said of Harper. “Last year, he gets hit in the face. This year, he has had a couple of injuries. It’s been a tough stretch for him.”

Outfielder Mickey Moniak will be called up from triple-A Lehigh Valley as the corresponding roster move. The Phillies are trying to get him to San Diego by Sunday, but are still working out the logistics of getting him on a flight in time.

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“There’s a flight that’s available to get him here [Sunday], but as you’re aware, there’s been a lot of problems with people making flights,” said Dombrowski, referring to the issues new callup Mark Appel had getting to San Diego on Saturday. “So, we’re hopeful he’ll be here in time for the game, but everything has to go smoothly. It’s a direct flight from Philadelphia, it gets here before noon.”

Dombrowski said he doesn’t think Harper’s injury will effect who they target during the trade deadline.

“I’m still hopeful we’ll play well,” he said. “We still have a good club. You don’t replace a person like him, but we’ve still got a good club, and a lot of good things about it. We’ve still got a lot of guys who can swing the bat, so all the guys will have to step up.”

The Phillies’ bats ignited after suffering the blow of Harper’s injury. After not scoring for the first four innings, the Phillies put up three runs in the fifth. J.T. Realmuto hit a solo home run, and Yairo Muñoz grounded out to drive in Alec Bohm. Kyle Schwarber added a single to score Didi Gregorius, giving the Phillies a 3-0 lead.

The Padres attempted to rally in the bottom of the fifth. Phillies starter Zach Eflin allowed his fourth hit, a two-run double off the bat of Jorge Alfaro. Bohm hit an RBI double in the sixth to give the Phillies a 4-2 lead.

Four relievers each worked a scoreless inning. Andrew Bellatti came in for Eflin in the sixth and struck out the side. Corey Knebel induced three flyouts in the seventh inning, Brad Hand had a strikeout and induced a flyout and a groundout in the eighth, and Seranthony Domínguez earned his second save with a 1-2-3 ninth.

Aside from a bumpy fifth inning, it was a promising outing for Eflin, who had been struggling with a bruised right knee. He went only two innings in his previous start, but went five on Saturday night. He allowed four hits, two earned runs, two walks and struck out three. He finished his night at 80 pitches.

Eflin said after the game that his right knee felt “fine” on Saturday. He’s going to see how he feels on Sunday.