Joining Estrada were infielders Travis Ishikawa and Cesar Izturis. Izturis was originally scheduled to begin his stint on Friday, but a rainout pushed him back a day.
"It changes when they're coming back, but that's all right," manager Ron Roenicke said. "We kind of rearranged that a little bit. We're also going to see how they're doing, and whether they need more than what we had planned."
Estrada was 0-3 with a 4.50 ERA before being placed on the disabled list on May 24 with a right quadriceps strain. Roenicke said the team plans on two rehab starts before he returns to the Major League rotation, but adjustments will be made if necessary.
Ishikawa and Izturis may re-join the Brewers for their series against the White Sox in Chicago that begins on June 22.
"We kind of had it mapped out," Roenicke said. "But those individuals know that if they need more games, they need to do that."