KANSAS CITY -- The Phillies placed right-hander Vince Velasquez on the injured list retroactive to Wednesday with a right forearm strain. The club will summon left-hander Cole Irvin, ranked as the Phils' No. 16 prospect by MLB Pipeline, from Triple-A Lehigh Valley to start in his Major League debut on Sunday against the Royals.

Velasquez said the trigger point for his concern came in his last start at St. Louis when he threw three consecutive sliders to Cardinals shortstop Paul DeJong and felt some discomfort. Velasquez had a bullpen session on Friday and he felt there was progress, but not enough to feel confident about starting the Interleague series finale at Kauffman Stadium.

"I threw 30-something pitches and everything seemed liked it was progressing," Velasquez said. "But there's something lingering that didn't give me the confidence to really start on Sunday. That's when I knew I needed to say something."

Velasquez is expected to be checked out Monday when the Phillies return home from this road trip.

"This is precautionary, from my standpoint," manager Gabe Kapler said. "He threw his bullpen at like 90 percent. I stood in for it. He threw some really good curveballs. We just felt like he made all his starts last year and has been very durable for us since I've been here. It made sense to just be a little conservative on this one."

The Phillies recalled left-hander Austin Davis and will make another roster move on Sunday to accommodate Irvin, who is 2-0 with a 2.25 ERA in 36 innings for Lehigh Valley.

"We're really excited to give [Irvin] this opportunity," Kapler said. "He has really earned it, having pitched very well at Triple-A. He's quick to the plate and has a history of throwing strikes."

When he returns, Velasquez made it clear his preference is starting rather than relieving. He's 1-2 with a 3.86 ERA in six starts.

"I'm still a starter," Velasquez said. "I have a lot to accomplish. I still have a lot of starts ahead of me."

Worth noting

Outfielder Aaron Altherr was claimed off waivers by the Giants on Saturday. Altherr was 1-for-29 at the plate in 22 games with the Phillies this season.