Hisashi Iwakuma threw four innings Sunday in a rehabilitation start with the Rainiers against the Las Vegas 51s.
Iwakuma allowed six hits and two earned runs. Three of the hits he allowed were first-inning singles. He threw 76 pitches, 54 strikes. He struck out two and walked none. The Mariners expected Iwakuma to be around the 80-pitch mark in his rehab start, which may be his only one before rejoining the Mariners' rotation.
Iwakuma, 33, is recovering from a strained ligament in his middle finger, which was diagnosed in early February and prevented him from pitching in spring training. He was 14-6 last season with a 2.66 ERA in 33 starts.