In 1 2/3 scoreless innings, Rosario struck out three Marlins and preserved the tie long enough for Hector Sanchez's walk-off bloop single.
"He only had one day off and that's a lot of pitches," Bochy said.
Rosario has thrown a combined 6 2/3 innings of relief in three appearances during the current Giants homestand and has not shied away from emotional reactions to some of the high-leverage outs he has recorded.
"You haven't seen anything yet," Rosario said Saturday. "I'm trying to control myself, but the things I do are crazy."
This is Rosario's second stint in the San Francisco bullpen in 2013. He was optioned to Triple-A Fresno on May 28 to make room for starting pitcher Mike Kickham after Ryan Vogelsong was placed on the disabled list. Rosario has a 2.84 ERA in nine games this season.
Andrew Owens is an associate reporter for MLB.com. Follow him on Twitter @OwensAndrew. This story was not subject to the approval of Major League Baseball or its clubs.