The Angels sent left-hander Andrew Heaney for an additional MRI exam Monday morning after the 24-year-old stopped throwing last week because of continued tightness in his left forearm.
Heaney headed to the disabled list on the season's third day after feeling tightness later diagnosed as a flexor muscle strain during his season-opening start. He resumed throwing earlier this month, and then stopped while the team was in Minneapolis.
Monday's MRI showed the same issue as the first one. Angels General Manager Billy Eppler said the team now intends to retest Heaney's strength each week until the tissue in his forearm is "fully healed."
That means it will be multiple weeks, at least, before he returns to action.
Heaney was the Angels' breakout starting pitcher one season ago after he was acquired for Howie Kendrick. He had a 3.49 earned-run average in 18 starts and opened 2016 as the team's No. 2 starter.
Because left-hander Tyler Skaggs felt abnormally fatigued after his Wednesday start for triple-A Salt Lake, the Angels scratched him from his scheduled Monday start, citing caution as their guide.
Another consideration, Eppler said, was the team's desire to keep Skaggs' season workload reasonable. He is returning from August 2014 Tommy John surgery.
Eppler would not say when Skaggs, 24, will next start.
"He'll focus on strengthening this week," Eppler wrote in a text message. "We'll gauge how he feels day to day and continue to be extra cautious with him."
Mike Trout served as the Angels' designated hitter for the first time this season on Monday. He is recovering from fouling a ball off his right foot Saturday. … Cliff Pennington started at second base for the second time in three days, both times against a right-handed pitcher. The Angels expect to face right-handed pitchers the next three nights. Manager Mike Scioscia said a platoon had not developed between Pennington and incumbent second baseman Johnny Giavotella, but acknowledged a "tandem."