A recent MRI showed no significant injury to McCullers' sore right shoulder, but Hinch says that ``there's just not enough time to build him up to the role we anticipate him doing.'' He added that the right-hander won't miss a significant amount of time.
As recently as the weekend, McCullers said he still had soreness in his pitching shoulder. He acknowledged then that he might not be ready to start the season.
"I can't really worry about [missing the start of the season]," he said. "I want to start the season obviously with the club. That's my 100 percent goal right now.
"But like I've discussed, 150 games are more important than those first two, if it comes to that."
McCullers, 22, made 22 starts as a rookie last season, going 6-7 with a 3.22 ERA and 129 strikeouts over 125⅔ innings.
McCullers' absence settles the Astros' season-opening rotation as Cy Young Award winner Dallas Keuchel, Collin McHugh, Doug Fister, Scott Feldman and Mike Fiers. Keuchel will start the opener April 5 against the Yankees in New York.
Information from The Associated Press was used in this report.