SAN DIEGO -- Eric Stults appreciated the support his bullpen gave him, especially since he was just one of them.
Stults (2-2) allowed all five hits in 5 1/3 innings in his first start since June 3. He struck out five, walked two and had a wild pitch.
"Any time as a starter, when you leave the game with a lead, I feel pretty confident," Stults said about the Padres bullpen.
"Those guys make it easy to catch," Padres catcher Eddie Rodriguez said. "They were really unbelievable."
Street pitched the ninth for his 19th save.
"Those guys, they come to pitch," Padres manager Bud Black said. "There is a resiliency and a mindset that you come to pitch."
Carlos Quentin reached on a one-out double in the fourth inning and scored on Alonso's single. After Cameron Maybin doubled, Alonso scored when Cabrera's soft liner deflected off the glove of second baseman Darwin Barney for an infield single.
Chicago was not able to take advantage of the few scoring chances it had, going 0 for 4 with runners in scoring position and stranding seven runners overall.
Stults, who last pitched in relief on Thursday, struggled with his command in the first inning. He allowed Barney's one-out double, then walked Alfonso Soriano with two outs before striking out Starlin Castro.
"That first inning was bad, kind of a grind," Stults said. "I threw a lot more pitches than I wanted to. After that I was able to get some quick outs."
Travis Wood (4-8) allowed two runs and five hits over six innings as he extended his career-high with his fifth straight loss. The left-hander struck out three and walked three.
"(Monday) was another grind," Wood said. "I was behind a lot of hitters but I was able to pitch out of a lot of stuff. We just came up a little bit short."
The Cubs' two prized prospects -- Brett Jackson and Josh Vitters -- both started and had tough nights.
Jackson, who got two hits in his major league debut Sunday against the Los Angeles Dodgers, struck out four times. Vitters, who also debuted Sunday as a pinch-hitter, was 0 for 4, including a groundout to end the sixth inning with runners at second and third.
"A tough day for the kids," Cubs manager Dale Sveum said. "That's what they're here for, to see this kind of pitching and make those adjustments."
Since his last start, Stults spent time on the disabled list with a strained left lat and made his last four appearances out of the bullpen. He was inserted into the rotation after Kip Wells was designated for assignment on Friday.
Cubs RHP Matt Garza (right elbow stress) was placed on the 15-day DL and will be out "indefinitely," according to GM Jed Hoyer. ... San Diego has won eight times in its last 10 home games. ... Cubs 1B Anthony Rizzo made his return to San Diego for the first time since the Padres dealt him to Chicago for RHP Andrew Cashner in a four-player deal in January. Rizzo, who went 0 for 4, was the centerpiece for San Diego in the four-player deal when he was acquired from Boston for 1B Adrian Gonzalez before the 2011 season. But after his highly anticipated arrival in San Diego in June 2011, the lefty hit just .141 with one home run and nine RBIs in 128 at-bats. Asked before the game if spacious Petco Park had anything to do with his poor offensive showing, Rizzo said, "The ballpark could have been a T-ball field and I wouldn't have hit the ball. I just wasn't hitting the ball." ... Cubs LHP Brooks Raley will make his major league debut on Tuesday night against LHP Ross Ohlendorf (3-2, 6.27 ERA).