Banister said the Rangers will go with Andrew Cashner and A.J. Griffin in their two-game series against the Mets on Tuesday and Wednesday. The Rangers are off on Thursday and then Cole Hamels will start on Friday against the Astros.
Perez, who allowed seven runs in 4 2/3 innings in an 8-4 loss to the Twins on Friday, would not return to the rotation until next Saturday at the earliest.
• Perez's struggles continue with 7 ER allowed
Perez did some video work after Friday's loss and said he may be tipping his pitches. Perez said he could tell a difference where his hands were when throwing a fastball and when throwing his offspeed stuff.
"My wrist was in a different position," Perez said. "I think it has been happening a lot. Let's see if that will be the difference. If not, I'm going back to Venezuela and throw rocks until I figure it out."
Brocail said there is more to it than that.
"He may be tipping pitches, but everything hit last night was middle across the zone," Brocail said. "You can tip and still get guys out and you cannot tip and throw the ball over the middle of the zone and not get hit. I don't want anybody making excuses. I don't want that to be a cop-out that makes us not work hard in our next side session."
Perez is 0-4 with a 9.41 ERA in his last four starts. For the season, he is 5-10 with a 5.46 ERA that is the second highest in the American League among qualifying pitchers.
"He feels that's something he needs to work on," Banister said. "But it comes down to execution of pitches the majority of the time."
T.R. Sullivan has covered the Rangers since 1989, and for MLB.com since 2006. Follow him on Twitter @Sullivan_Ranger and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.