Santiago, who was pulled from his rehab assignment earlier in the week, is aiming to resume throwing in 3-to-5 days, though that will likely depend on how he responds to treatment. An updated timetable for his return should come into focus once he is able to get back into his throwing program.
Despite riding a modest four-game hit streak, Smith will head to the bench for a breather after starting three of the past four games at backstop. In his place, Omar Narvaez will set up behind the dish, batting seventh.
Engel is just 1-for-9 with four strikeouts over his last three contests, so he'll get the day off after starting seven straight games in center field. Leury Garcia will take over for him in center field, opening up a spot for Nicky Delmonico to pick up a start in left field.
After throwing four consecutive days, Price was held back from throwing Wednesday. "Yesterday when he threw, I don't know that he felt as free as he did the three consecutive days in New York," manager John Farrell said on Wednesday. He's expected to go through treatment and hopefully resume throwing Thursday, though that will depend on how he feels. Price was shut down multiple times while trying to recover from the same issue earlier in the season, so the Red Sox are likely trying not to push him the second time around.
Everything apparently went well, and Harris is now set to face live hitters for the first time since landing on the disabled list at the end of July. Barring any setbacks, Harris could head out on a rehab assignment following Friday's session. The 32-year-old, who owns a healthy 2.86 ERA and 0.95 WHIP across 34.2 innings this season, is expected to reclaim his role as the Astros' primary setup man once he returns.
The Astros are hopeful the injection will reduce the swelling above McCann's knee within a few days, at which point the team will determine the next step in the catcher's recovery process. At this point, McCann doesn't look to be at risk of a lengthy stay on the 10-day disabled list, but a more definitive timetable for his return won't be established until he's cleared to resume baseball activities.
Wednesday marked his second bullpen in as many days, and the Astros will likely wait and see how McCullers responds to Wednesday's activity before deciding on his next step. He'll still need to progress to facing live hitters before he embarks on a rehab assignment, but he's inching closer to a return to the big-league rotation. A clearer timetable for his return should start to come into focus as he continues to progress in his throwing program.
Gattis passed his initial ImPACT test and appears set to begin ramping up his activities in preparation for a return, likely at some point during the Astros' current homestand. According to Kaplan, manager A.J. Hinch said that the team plans to send Gattis out on a rehab assignment prior to activating him from the 7-day disabled list, though any stint in the minors would likely be a brief one. In the meantime, the Astros will get by with Juan Centeno and Max Stassi as their catchers while both Gattis and Brian McCann (knee) are sidelined.
Grossman will give way to Eduardo Escobar at designated hitter after going 2-for-19 at the plate over his last five starts. While Grossman has been a boon for those in leagues where on-base percentage is a category thanks to his .367 mark, his statistical portfolio has been otherwise underwhelming this season, making him a low-upside fantasy option in most traditional 5x5 formats.
When he takes the mound Thursday, it will mark Diekman's first appearance in a professional game since Oct. 9, 2016. The 30-year-old has faced a long road to recovery while undergoing three surgeries to repair and rebuild his colon, but he finally seems to be progressing toward a return after facing hitters in live batting-practice sessions and simulated games on multiple occasions in August. He's expected to throw 15 pitches in his first appearance for Frisco and may only need one or two minor-league outings beyond that before the Rangers activate him from the 60-day disabled list.