Phillies place Aaron Nola on DL with lower-back strain

Aaron Nola was placed on the disabled list on Monday afternoon because of a lower-back strain, but the Phillies expect the righthander to miss just one or two starts.

General manager Matt Klentak said Nola felt soreness in his back during his last start, April 20 against the Mets. Nola, 23, allowed four runs that night in five innings. He has a 4.50 ERA in his first three starts of the season after missing the final two months of last season because of an elbow injury.

Nola elected against having elbow surgery, and there were concerns before the start of spring training about the pitcher's health. Manager Pete Mackanin said he feared that Nola would knock on his door and deliver bad news. But those worries were focused on Nola's elbow, not his back. The Phillies are relieved that it's not a serious injury.

His placement on the 10-day disabled list is retroactive to April 21, meaning Nola can be activated as early as next Monday.

"After receiving treatment over the last few days, the symptoms improved, but he still felt some tightness during his side session yesterday," Klentak said.  "Our hope and expectation is that this will not be a lengthy DL placement and that Aaron will miss only one or two starts."

Nola was scheduled to pitch Wednesday night against Miami at Citizens Bank Park. That game will likely now be the major-league debut for Nick Pivetta, who is scheduled to pitch Wednesday for triple-A Lehigh Valley.

Pivetta was just another arm after being acquired in 2015 from Washington for Jonathan Papelbon. But he thrust himself into the mix of the young pitchers the team has assembled at double A and triple A. The 24-year-old had a strong season last year and has allowed just two earned runs this season in his first three starts. He has 24 strikeouts and two walks in 19 innings.

"We're all searching for the same goal here," Pivetta said during spring training. "We all want to play in the big leagues with this team. I wish everyone could do the same as me. We all want to. We're driving every single day to go out and play hard and achieve their goals, too."

Pivetta impressed during his time in major-league spring training. He picked the brains of the veteran pitchers and even spent time with Roy Halladay, whom Pivetta idolized while growing up in Canada. The pitcher pairs his mid-90s fastball with a curveball and slider.

"Very crisp breaking ball, location has been really good," Klentak said on Saturday. "He's growing up as a pitcher. He's been pretty outstanding so far through three starts. We're pretty pleased with that."