"He felt good," manager Trey Hillman said. "He started to fatigue, which is normal, but the tightness didn't come back, which is good."
"He'll stay with us for a couple of days, go back to Kansas City. He'll probably do another bullpen [session] just to be safe before we send him back out."
Farnsworth went on the disabled list June 26 with a right groin strain. He's 1-4 with a 4.24 ERA in 27 games.
Outfielder Josh Anderson, acquired from Detroit Thursday, still had not reported as he and his wife await the birth of their first child.
"I haven't heard a word," Hillman said, adding that he planned to call Anderson after Sunday's game.
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.