WEST PALM BEACH, Fla. -- Because he hasn’t progressed to the point where he can start facing hitters on the back fields, Astros pitcher Justin Verlander will have to start the season on the injured list. Manager Joe Espada made the announcement Tuesday after discussing it with Verlander and other team officials.

Verlander reported to camp two weeks behind schedule because of a shoulder issue and has been limited to throwing regular bullpen sessions over the past couple of weeks. He’s yet to face hitters, and with Opening Day less than three weeks away, Verlander ran out of time to get fully ready for the start of the season.

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“I’m just trying to trust my body and not rush anything because of a date on the calendar being Opening Day, and just trying to do things the right way,” he said. “I thought we were really close to being able to make it happen, but it was really on the fast end of things pace-wise to build up. I think once we kind of all sat down, the calendar dictated ‘All right, we need to make a decision.’”

The good news for the Astros is that Verlander hasn’t had any setbacks and remains encouraged with how he’s feeling. He’s particularly encouraged by his bullpen side session on Sunday in which he threw 60 pitches and walked away feeling great about his progress.

"Would I like to be out there for Opening Day? Absolutely. Am I frustrated? Absolutely. Am I excited about the way I feel right now? Also yes,” he said. “I’m trying to see the forest through the trees here and look at the bigger picture and try to be the best pitcher I can be for the whole season, except for the first week or two.”

Verlander would like to throw one more bullpen session before facing hitters for the first time. His next bullpen session is tentatively scheduled for Friday, but his timeline is a moving target.

“I don’t have any of the answers, and the frustrating part about this is nobody has the answer,” he said. “It’s, ‘OK, when am I healed, when am I full go?’ I’m hovering at 90 percent right now. I feel like I’m ready to bump it up. Does going from 90 percent to 100 percent take a little longer, or is it like, ‘All right, I’m good’? I don’t know. I’ve got to continue to build up, and I think we’ll know when the time is ready. Maybe there’s a potential for a follow-up MRI to see how things look, making sure it is still good, which it was before.”

Astros general manager Dana Brown remains positive because of how strong Verlander looked in his most recent bullpen session.

“He had the same throwing actions with pretty good arm speed, so I wasn’t concerned,” he said. “When the throwing actions are different, that’s when it’s like, 'Something’s bothering this guy,' and I didn’t see that. He had a little zip on the ball. I think he’s going to gradually start to increase his velocity, and that’s going to take a little extra time.”

Verlander, who was traded back to the Astros from the Mets in August, also experienced a delayed start last year with the Mets as he was placed on the injured list with a right arm injury on the eve of the regular season. He debuted on May 4 and made 16 starts for New York before the Astros acquired him at the Trade Deadline.

Verlander went 7-3 with a 3.31 ERA in 11 regular-season starts (68 innings) in his return to Houston and made three postseason starts before the club was eliminated by the Rangers in the ALCS.

The three-time Cy Young Award winner is entering the second season of a two-year deal he signed with the Mets last winter. The contract contains a $35 million vesting option for 2025 that is triggered if Verlander throws 140 innings this season. The Mets will pay half of the option if it vests.