HOUSTON -- Astros manager AJ Hinch informed lefty Framber Valdez on Sunday morning that he would pitch in the bullpen for the remainder of the regular season, meaning the club will go with a four-man rotation for the final three weeks.

Because of off-days, the fifth spot in the rotation will come up only two more times -- Wednesday against the A’s Sept. 28 at the Angels in the penultimate game of the season. Hinch said the club will use relievers to piece together those games.

The Astros’ bullpen will have 12 relievers once Valdez is able to pitch again Tuesday. Valdez has a 5.62 ERA in 23 games with 40 walks in 65 2/3 innings this year, including a 7.07 ERA and 23 walks in 35 2/3 innings in eight starts.

“We really only need four starters for most of the rest of the season,” Hinch said. “Right now, he’s going to sort out his delivery and his command and control in the bullpen and see if he can help us down the stretch.”

The way the starting pitching lines up, Justin Verlander, Gerrit Cole, Zack Greinke and Wade Miley will each have four starts remaining.

Correa hits on the field

Astros shortstop Carlos Correa took batting practice on the field Sunday for the first time since suffering lower-back soreness in a game Aug. 19. Correa also took grounders from Hinch at shortstop and did some agility drills in the outfield, all without any pain.

“Big step, not only getting to take ground balls but feeling great out there,” Correa said. “Obviously, it feels really good to be out there with the guys working every day. It’s just one step closer to me getting back. I’m excited.”

Correa said he would take batting practice on the field again Monday before taking the day off Tuesday. At that point, he could progress to taking live batting practice or be sent out on a Minor League rehab assignment. Triple-A Round Rock and Class A Fayetteville were playing elimination games Sunday in the playoffs, so Correa might have to settle for live batting practice if they both lose.

Round Rock beat Iowa, 10-5, in Game 5 of the Pacific Coast League American Conference Championship Series to advance to the PCL Championship, which begins Tuesday in either Las Vegas or Sacramento.

“The hitting on the field is the most encouraging part of that,” Hinch said. “If that goes well, we could really start to be aggressive with what comes next for him.”

Worth noting

• All-Star reliever Ryan Pressly, who had surgery on his right knee late last month, threw an extensive bullpen session on Sunday, which is something he has been pushing to do for the last few days. The Astros held him back to make sure there’s no inflammation in his knee. He’ll throw a couple more and progress to live batting practice, but it appears there’s a good shot he could return before the end of the regular season.

• The throwing program for right-hander Brad Peacock, who went on the inured list Aug. 28 for the second time with right shoulder discomfort, is going “really, really well,” Hinch said. “The first time he was a little nervous, didn’t want to really let it go. [Saturday], he threw a little bit harder and he’ll do that again over the next couple of days.”

• First baseman Yuli Gurriel, who left Friday’s game with left hamstring discomfort, is still day to day. Hinch said Sunday he feels really good and has no symptoms. He’s scheduled to run Monday. The club is targeting his return on Tuesday or Wednesday against the A’s.