The Phillies were unable to activate Didi Gregorius from the injured list Monday as the shortstop’s elbow remains swollen nearly two weeks after he said he didn’t know why he had a “huge bump” on his right arm.

Gregorius is with the team in Miami but the swelling on the outside of his elbow is preventing him from swinging or throwing. Monday was the first day he was eligible to return from the injured list.

“As of yesterday, it had not completely gone away,” manager Joe Girardi said, “which is kind of strange. We’re trying to get it out but we do feel it’s better than it was.”

Gregorius first injured the elbow in April when he landed hard while chasing down a fly ball in shallow center. He missed three games after the Phillies drained the fluid from his elbow. But the swelling returned earlier this month, causing Gregorius to now miss 11 games. When ready, Gregorius will likely have to complete a minor-league rehab assignment before returning as his absence has been so extended.

» READ MORE: Phillies’ Didi Gregorius ‘worried’ about recurrence of swelling in his elbow

He said they planned to let the swelling work itself out this time instead of draining it. Gregorius was diagnosed 10 years ago with a kidney condition, which he said causes his body to take longer to get rid of inflammation. The Phillies have still not determined why the shortstop’s elbow became swollen.

“It could have happened on a swing, I guess,” Girardi said. “But we don’t really have like a glaring reason why it swelled up.”

Harper’s day off

Bryce Harper was out of the lineup for a second-straight day as the Phillies are hoping consecutive days off can turn around his rough month.

“I went to bed last night, woke up this morning, and said ‘You know what. I’m going to give him another day,’ ” Girardi said. “That’s the reason.”

» READ MORE: Bryce Harper is slumping and ‘tired of seeing it’ | Extra Innings

Harper entered Monday with two hits in his last 25 at-bats. His OPS (.884) is still well above league average, but it is 179 points lower than it was at the start of the month. He has 26 strikeouts this month in 57 at-bats after striking out 19 times last month in 78 at-bats.

Harper has been slowed this month by injuries, but Girardi said Monday that he does not believe Harper’s sore shoulder is still affecting him.

“He has not said anything about it,” Girardi said. “I chose to give him another day off. He’s been struggling. Players go through this and sometimes a couple days can help.”

Maton vs. lefties

Nick Maton has had success this season against left-handed pitching, but he was held out of Monday’s lineup against a left-handed starter.

The Phillies instead played Ronald Torreyes at shortstop against Trevor Rogers as the right-handed Torreyes has six hits in 12 at-bats since returning from the injured list.

» READ MORE: Phillies rookie Nick Maton has a mindset like Chase Utley and a text message from Jayson Werth

Maton entered Monday hitting .371 (13 for 35) with a .971 OPS against left-handers. In 2019, Maton hit just .254 in the minors with a .673 OPS against left-handers. The rookie said his success this season is a result of the work he received last summer in Allentown when he was used as a left-handed hitter for the southpaws to get work at the team’s alternate training site.

Maton said he and Bryson Stott would rotate every other at-bat last summer against the hard-throwing left-handers who were training in Allentown.

“It ‘s just repetitions,” Maton said. “Seeing that many reps helped me out immensely. It’s crazy. A night and day difference.”

Extra bases

Scott Kingery remains on the injured list with a concussion, but he is in Allentown working out. He’ll likely join triple-A Lehigh Valley when he’s activated. ... Vince Velasquez will start Tuesday against right-hander Sandy Alcantara. Velasquez threw 18 pitches on Friday night, a session that Girardi is treating like his bullpen session. The team said his numb finger is no longer an issue.