Astros manager Bo Porter said the move to scratch Peacock is precautionary.
"You start to think about erring on the side of caution, even though the bulk of the soreness is behind him, but today being his start day it made sense to go ahead and skip him and give him the extra time before he takes the ball," Porter said.
Peacock, 26, began the season in the bullpen before making his last six turns in the rotation. In his last start, he picked up his first win of the season, tossing 6 2/3 innings and allowing two runs en route to an 8-2 win over the White Sox. He is considered day to day.
"Obviously, it's not a DL situation," Porter said. "We we didn't want to risk it or push it when we can push him back and bring somebody in to make this start, and hopefully he'll take his turn five days from now."
Zeid, 27, has made seven appearances for the Astros this season across two Major League stints. He's posted no record and a 3.86 ERA with eight strikeouts in seven innings.
"Josh Zeid got pretty much got caught in the numbers game," Porter said. "It's one of those things where obviously he has an option. Looking at Peacock's situation, it's not a DL situation but we want to keep him in the rotation. You don't want to risk him being out for 15 days."
Brian McTaggart is a reporter for MLB.com and writes an MLBlog, Tag's Lines. Follow @brianmctaggart on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.