Gasper went 1-for-3 with a solo home run during the Red Sox's 3-2 loss to the Royals on Friday.
Pecko did not factor into the decision in Friday's 3-1 loss to the Rays, allowing one run on one hit and two walks with four strikeouts over 5.2 innings.
Gray (17-5) was tagged with the loss in Friday's game against the Royals, allowing three runs on six hits and two walks while striking out five across six innings.
Astros manager Joe Espada told reporters that Alvarez is not in the starting lineup against the Rays on Friday due to a right ankle injury, Chandler Rome of The Athletic reports.
Alvarez is not in the Astros' starting lineup against the Rays on Friday, Brian McTaggart of MLB.com reports.
The Red Sox recalled Seigler from Triple-A Worcester on Friday.
Boston placed White on the 10-day injured list with a right foot ligament injury Friday, retroactive to Sept. 9.
Rutschman (elbow) will start at catcher and bat third in Friday's game against the Royals.
Hader struck out one in a clean ninth inning to earn the save Thursday against the Phillies.
Campbell was placed on the 7-day injured list at Triple-A Worcester on Thursday with a left foot contusion, Chris Cotillo of MassLive.com reports.
