Vince Velasquez is dealing with an oblique injury, which could test the Phillies’ pitching depth after the right-hander became the third starter this week to suffer an injury.

Velasquez felt a tweak, manager Joe Girardi said, before he pitched Sunday in a simulated game. The timeline for an oblique injury can vary, but they often seem to linger.

“He went through the sim game and didn’t tell us,” Girardi said. “Guys do that all the time. The next day it kind of presented itself. We’ve taken it slow with him, knowing that we have to build him up and we don’t want to go too soon with these sort of things.”

Zach Eflin felt discomfort in his back last Saturday and was scratched Friday night from his start in Tampa against the Yankees. Spencer Howard experienced back spasms on Monday morning and was unable to pitch that afternoon.

Eflin, Howard, and Velasquez made progress on Friday, but it’s unclear when they will be able to pitch in a game. The Phillies hope Eflin and Howard can throw bullpen sessions on Sunday after throwing Friday from 120 feet. Velasquez threw Friday from 60 feet and felt good, Girardi said.

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If Eflin can throw Sunday without issue, he would be scheduled to start a Grapefruit League game next week and be in position to be ready to start the third game of the season.

Eflin is the team’s No. 3 starter while Howard and Velasquez appear to be on the outside of the team’s rotation competition. But they were expected to start the season as important depth pieces ready to slide into the rotation in the event that a pitcher like Eflin suffered an injury.

Now all three are injured, leaving it uncertain who the team’s fifth starter would be at this time if they needed one. Ivan Nova started Friday night’s game in Tampa, but he’s on a minor-league deal and it would be tough to add the right-hander to the 40-man roster for a spot start. Instead, Girardi said they would probably “piece it together.”

“You take it day by day,” Girardi said. “I came in today and saw everyone go through everything and I was like ‘Man, this is a good day.’”

Realmuto, Haseley progress

J.T. Realmuto could play in a Grapefruit League game next week after he played Friday in a simulated game in Clearwater. The catcher’s thumb, Girardi said, continues to heal and he remains on track for opening day. He would play first as a designated hitter before catching.

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Adam Haseley also played in the simulated game and Girardi said he’s “ahead of schedule” in his return from his groin injury, but it’s too early to say if he can re-enter the team’s center-field competition. He’ll test his groin Sunday by running the bases before he can play a Grapefruit League game.

Extra bases

Didi Gregorius is in the concussion protocol after being hit in the head earlier this week by a pitch. He could play Saturday against Toronto. ... Brad Miller (oblique) could play a Grapefruit League game by the end of next week. ... Connor Brogdon (rib) could pitch in a game this weekend. ... Matt Moore will start Saturday.