Andrew Bellatti has a 1.64 ERA over his last 11 outings at triple A. Could he help the Phillies now?

When Andrew Bellatti was sent down to triple-A Lehigh Valley on May 23, he saw an opportunity. The right-handed reliever had a 5.68 earned run average in 15 appearances and had been struggling to throw strikes, walking hitters at a 15% clip, the highest mark of his big league career. He was also struggling to get out lefties, who had a .421 on-base percentage against him.

To even out those splits, the Phillies told him to work on developing his changeup. Bellatti hadn’t thrown it much before, relying primarily on his four-seam fastball and his slider, but he has started to incorporate it more. The early returns have been good. Through Saturday, Bellatti had posted a 1.64 ERA through 11 outings at Lehigh Valley. He had yet to walk a batter.

Bellatti’s stuff has ticked up, too. On Friday, his slider was at 88.5 mph, up from his season average of 87.7 mph. His four-seam and changeup were up a bit, too.

He said he’s adjusted his thumb placement from the side of the ball to underneath it, to make the changeup grip feel more comfortable. That fix — combined with a change in his mindset — has helped him throw it for strikes.

“[The changeup] is coming along nicely,” said Bellatti, who turns 32 in August. “I think it’s more mentally not trying to make it something that’s it’s not going to be and trust it in the zone, and throw it with the same mentality as I would throw my fastball.

“Before, I was pronating it early, causing it to leak more arm-side earlier instead of delaying the pronation like a fastball to make it a strike longer. Now, I’m not trying to manipulate it to make it move more. I’m just letting my natural arm action provide the movement.”

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The Phillies could use Bellatti’s help in the bullpen. Seranthony Domínguez remains on the injured list with a strained muscle in his left side, and likely won’t be back after the minimum 15-day term. Dylan Covey hasn’t proved to be trustworthy. Matt Strahm has already exceeded his innings pitched from last season, and is starting to show the wear and tear of that extra workload.

Manager Rob Thomson said he’s been happy with how Bellatti has pitched, but he would still like to see him throw more changeups.

“I think he’s doing what we asked him to do, for the most part,” Thomson said. “Which is to throw strikes, fill up the zone, use his other pitches, and he’s doing that. Both him and [fellow reliever Connor] Brogdon are really throwing the ball well right now.”

Bellatti said he’ll continue to embrace the opportunity.

“I’m just taking advantage of this time,” he said. “Being grateful and finding enjoyment in the work it takes to get back.”

Andrew Painter (sprained UCL in his right elbow) will throw his next bullpen session on Monday or Tuesday in Clearwater, Fla. … Fellow right-hander Noah Song (low back strain) is expected to begin his rehab assignment at low-A Clearwater on Thursday.

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