After making four relief appearances once he came off the disabled list at the end of July, the 32-year-old's last two outings have been starts, and good ones at that.
In 13 combined innings, Stults has allowed just one run on 10 hits while striking out eight.
The lefty will look to continue his stellar run Saturday when the Padres take on the Giants in the second game of the weekend series.
In his last start, Stults kept the Braves scoreless into the eighth inning before leaving after 7 2/3 innings and surrendering one run while the Padres earned the victory.
"He frustrated us. He got us out of our normal game plan of seeing pitches and working the count a little bit and go deep in the count," Braves manager Fredi Gonzalez said after the game. "He really, really was frustrating to hit off of. ... We weren't our normal selves."
Stults hasn't pitched against the Giants since 2009, but when he did, he delivered a four-hit shutout.
Opposing Stults for the Giants will veteran lefty Barry Zito. The 34-year-old put together a so-so start his last time out against the Rockies, serving up four runs on seven hits over 5 1/3 innings.
"I lost my rhythm kind of through the middle innings," Zito said. "But in the front and back of the outing, I felt pretty good about eliminating the timing issues that make the command go away."
Giants: Mota return up in the air
Manager Bruce Bochy said that he hasn't considered the appropriateness of bringing back right-hander Guillermo Mota from his suspension for performance-enhancing drug use.
Mota, who received a 100-game suspension May 7, is eligible for reinstatement Aug. 28. He's currently trying to pitch himself back into shape during a Minor League rehabilitation assignment in the Rookie-level Arizona League, where he has allowed seven runs on eight hits in 2 2/3 innings spanning two games.
"We'll cross that bridge when we get a little closer," Bochy said, regarding Mota's impending playing status.
The Giants announced Thursday that they recalled right-hander Eric Hacker from Triple-A Fresno to fill Mota's long-relief role.
Padres: Grandal returns
The Padres activated rookie catcher Yasmani Grandal from the disabled list Friday. He batted fifth while starting behind home plate. Grandal was placed on the disabled list July 31 after straining his right oblique on a swing in Cincinnati.
Grandal caught his first game since the injury Thursday night in Lake Elsinore, Calif., as the Class A Storm dropped a 6-3 decision to the Inland Empire 66ers. He was 0-for-3 in the game, but did throw out a runner trying to steal second.
"The result for me wasn't the priority; the timing, getting in the game, having situations was the main thing for me," Grandal said. "One of the reasons I went down is to get a couple of in-game swings because it's a different swing. ... During [batting practice], you might go 60, 50 percent just so that you don't redo it again. ... It seems like it's back to normal."
Luke Gregerson has not allowed a run in his last 18 outings, including a scoreless frame in the eighth Friday.
Friday began a stretch in which the Giants will play 12 of 16 games on the road.