In four combined starts this season when facing the opposite club, the pitchers are 0-4, surrendering 16 earned runs over just 21 2/3 innings.
Both starters will try to reverse their fortunes when they meet Wednesday in the third game of the teams' three-game series in San Francisco.
Hoping to seal a series victory for the Giants, Bumgarner will try to win his first game since Aug. 20. The 23-year-old is coming off a subpar outing against the Cubs, giving up five runs (four earned) over four innings of work.
One of the runs Bumgarner allowed came when he failed to back up catcher Buster Posey on a throw to home plate.
"I was just acting like a baby and being stubborn with myself and it cost us another run. You never want to do that," Bumgarner said after the game. "That won't happen again."
As for Cahill, he will be pitching for his first victory since July 30. The 24-year-old tallied a 5.08 ERA over his six starts in August.
In his last outing, Cahill tossed 5 2/3 innings against the Dodgers, serving up three earned runs on four hits, taking a no-decision for his effort.
Two starts ago, the right-hander turned in his shortest outing of the season, lasting just 3 2/3 innings against the Padres while pitching on short notice after the trade of Joe Saunders to Baltimore.
"I wasn't on my normal program, but I felt like I should've been able to adjust," Cahill said after the game. "I wasn't able to do that. It's not an excuse. I had plenty of time to prepare; I didn't execute. I didn't throw the ball real well and when I did make good pitches, they found holes."
Giants: Club adds three players
The Giants recalled pitchers Dan Runzler and Dan Otero and purchased the contract of infielder Emmanuel Burriss from Triple-A Fresno on Tuesday. The Giants designated pitcher Eric Hacker for assignment to make room for Burriss on the 40-man roster.
Burriss hit .214 in 52 games before getting designated for assignment July 28.
"It's good to see these guys again," Burriss said. "Sometimes you don't know when the next time you'll see your friends and teammates again, and it's good to be back with these guys in the clubhouse again."
Burriss was hitting .274 in 29 games with Fresno before getting called up again, which he found out about Tuesday morning. He is expected to be used as a utility infielder, specifically as a pinch-runner and defensive replacement.
"He's been playing well," Giants manager Bruce Bochy said. "He went down to Fresno and played hard and played well. He earned this."
D-backs: Young could miss a week
Chris Young was prepared for the worst Tuesday morning when he tested out his right quadriceps muscle.
"This morning I thought I was going to wake up and it was going to be real sore, and it wasn't too bad," Young said. "I haven't run or anything, but hitting is fine and range-of-motion stuff is fine, so I don't think it's anything serious. Just a little nagging injury, and I'll try to get it right as soon as I can."
Young felt the quad "grab" while running to first base in the eighth inning Monday afternoon.
D-backs manager Kirk Gibson said it was likely that Young would be out three to seven days, so the club brought up outfielder Adam Eaton from Triple-A Reno.
Young said he has not thought about what Eaton's promotion might mean for his playing time.
"Not really my call," Young said. "The team is free to do whatever they think is right. As far as I know, we're still trying to win games and that's all we're focusing on right now. I don't really think about anything any deeper than that."
The D-backs have committed one error in their last six games and only five errors in their last 18 games since Aug. 18.
The Giants have 34 players on their active roster (17 pitchers, three catchers, nine infielders and five outfielders).