McCullers (forearm) has yet to resume throwing, Chandler Rome of the Houston Chronicle reports.
It's been three weeks since McCullers suffered a right forearm strain while throwing a bullpen session. The Astros quickly ruled the right-hander out for Opening Day after the injury, so it's not terribly surprising that he hasn't been cleared to resume throwing yet. Given McCullers' history of arm issues -- which includes a similar injury that he had last season -- the Astros will exercise the utmost caution here.