Manager Ozzie Guillen said his slumping players are on notice that they'll lose playing time or even get demoted unless they start producing.
Guillen said the names of seven players were discussed during a 35-minute meeting with front office officials after Thursday night's 8-2 loss to Atlanta before the decision was made to send out outfielder Bryan Petersen.
Petersen, who hit .212 in 22 games, was optioned to Class AAA New Orleans, and Guillen said more players could join him.
"It's a warning. They better step it up," said Guillen, who did not identify the other six players who were discussed in the meeting.
"I don't make the moves, but in case they don't know, just be aware because you never know what's going to happen. They should be aware now. They need to look at themselves in the mirror and say, 'Wow, why Petey and not me?' "
First baseman Logan Morrison was on the bench Friday in the 5-1 loss to Tampa Bay and will not play in Saturday's game, either, according to Guillen.
Morrison did not get a hit in 11 at-bats during the Atlanta series, and his average has fallen to .216.
Guillen said Morrison was pulled out of the lineup to help him "relax" and so that he can work on a few things in the batting cage.
"I want to give him a couple of days to go back to what he was," Guillen said. "It's not a punishment. He needs a break, mentally more than physically. We cannot win without LoMo hitting well. We need his help."