"Gil threw very well and had very live stuff," Royals manager Ned Yost said.
Meche, who decided against shoulder surgery, is hoping to pitch out of the Royals' bullpen for the rest of the season. He made his last start May 26 and is now on the 60-day disabled list.
The Omaha club will return from a West Coast trip to play Memphis on Saturday night.
Yost reported that another disabled starter, right-hander Luke Hochevar, threw a good bullpen session on Wednesday.
Hochevar had a another reason to celebrate. At 5:40 a.m. CT on Wednesday his wife, Ashley, delivered their first child, a daughter, named Laney.