Aaron Nola made his first rehab start on Wednesday and took a big step towards returning to the Phillies' rotation.

Nola threw four innings for Triple A Lehigh Valley, allowing one run on four hits. He threw 37 strikes out of his 52 pitches. The 23-year-old starter had three strikeouts and no walks while facing the Rochester Red Wings, an affiliate of the Minnesota Twins. Nola topped out at 93 mph during the outing.

Nola has been on the disabled list with a back strain four days after his last start on April 20. Manager Pete Mackanin said Nola will likely need two rehab starts before returning to the rotation. Barring a setback, that would leave him on pace to return with the Phillies either during their series in Pittsburgh May 19-21 or when they return home to face the Rockies May 22-24.

After finishing last season with an elbow strain, Nola made three starts in April. He had a 4.50 ERA and two wins in 16 innings, allowing just one home run and striking out 15. However, he gave up plenty of baserunners, giving up 20 hits while walking six. Opposing batters hit .317 off the righty.