DETROIT -- Astros right-hander Lance McCullers, who went on the disabled list Aug. 5 with a muscle strain in his right forearm, took a big step toward his return to the active roster Tuesday, when he threw 40 pitches in two simulated innings in the bullpen at Comerica Park.
"Another very positive day," McCullers said. "I threw about 40 pitches in the 'pen split over two different sections, so I got up and threw about 15 or 20 [pitches], sat down for five minutes, got back on the mound and threw another 15 or 20 and simulated a batter at the end, threw all my stuff -- fastball, sinker, changeup, curveball. Everything felt good coming out. Really happy with how it went."
McCullers will likely next head to the team's Spring Training facility in West Palm Beach, Fla., to throw to hitters in the instructional league, where players are about to report. Astros manager AJ Hinch said McCullers will pitch twice to hitters, with the goal of throwing two innings.

"Our hope for him is the ability to bounce back, and if you start thinking about scenarios, I would need to use him in a game if he needs to come in and get a hitter out, I'd like him to go back out to the next inning," he said. "It's literally just building him up to the point of being able to sit down in between -- have high intensity, a sitdown, high intensity again. A two-inning stint is something we're gearing for."
McCullers went 10-6 with a 3.93 ERA in 22 starts this year before hurting his elbow on Aug. 4 at the Dodgers. When McCullers returns, he will be in the Astros' bullpen for the rest of the season and the postseason. McCullers made two relief appearances in the playoffs last year, including throwing four innings to close out Game 7 of the American League Championship Series against the Yankees. He also started three playoff games, including Game 7 of the World Series.

McCullers said knowing that he will be used exclusively in the bullpen this postseason will help make the transition to reliever easier.
"At least now I'll know my role for sure," he said. "Last year, my role was up in the air. … Being in the 'pen and being successful in the 'pen is definitely a job in itself. There's definitely an art to it. Having veterans like Will [Harris], having a guy like Collin [McHugh], who has just transitioned from being a starter this year in the 'pen and how well he's thrown the ball, will definitely help me with that full-time with the job I have this postseason."
Peacock diagnosed with hand, foot and mouth disease
Relief pitcher Brad Peacock was sent home to Houston after being diagnosed with hand, foot and mouth disease, Hinch said. He's the third known Major Leaguer to contract the virus this season, joining Noah Syndergaard of the Mets and J.A. Happ of the Yankees.
The infectious disease, which most often occurs in children, comes with symptoms that include fever, sore throat, a headache and small blisters. Hinch said Peacock reported the illness when he flew with the team from Boston early Monday morning and was sent to Houston. It's unclear how long he will be sidelined.
"When we landed in Detroit, he reported the symptoms to our medical staff and we kept him away from the ballpark, and as things got a little bit worse for him, we sent him back home to Houston," Hinch said. "I don't know what that means in terms of a timeline or what it means for him, but because of the nature of the issue we wanted to keep him away from the team, obviously, to protect all of us."
Worth noting
• All-Star outfielder George Springer has been dealing with a sore left thumb since he spent 10 days on the disabled list a month ago with a sprained left thumb and was out of the lineup Tuesday. Springer took a couple of uncomfortable swings Monday, which Hinch noticed. But Hinch said Tuesday he had planned to give Springer the day off anyway and that he would return to the lineup Wednesday.
"He's going to play through any sort of discomfort," he said. "If it starts to hurt a little bit more, then I'll need to address it."
• Hinch revealed his starting rotation for this weekend's series against the D-backs: Dallas Keuchel will start Friday, Charlie Morton will start Saturday and Justin Verlander will start Sunday. Hinch said that will give Morton a full week between starts as he seeks to get him extra rest down the stretch.