SAN DIEGO -- The San Francisco Giants start what they hope is a long second half when they face the San Diego Padres on Friday night at Petco Park.

The Giants, with baseball's best record at 57-33, have their sights on keeping their recent tradition alive. Since 2010, they've won the World Series in even years.

"We're in the business of winning around here," Giants manager Bruce Bochy told mlb.com

The Padres (38-51) are trying to avoid something they're known for: delivering losing baseball. San Diego starts its second half hoping to sidestep its six consecutive season under .500 and begins the second half without left-hander Drew Pomeranz, who was reportedly traded to the Boston Red Sox.

San Francisco offers ace lefty Madison Bumgarner (10-4, 1.94 ERA)against Padres right-hander Andrew Cashner (3-7, 5.40).

For Bumgarner, a four-time All-Star, it's his second outing at Petco Park in four days. Although the other one was merely a bullpen session before Tuesday's All-Star Game that he didn't pitch in.

Bumgarner's left arm was still rebounding from pitching a one-hitter on 117 pitchers in a 4-0 blanking of the Arizona Diamondbacks Sunday.

So it's a well-rested Bumgarner looking for the Giants' 10th straight win over the Padres this season in kicking off an eight-game road trip. The Giants have also claimed the last six series against their most southerly NL West foes.

Bumgarner has won two of his last three decisions and was back being his dominant self against Arizona. He had a no-hitter in the eighth inning and struck out a career-high 14.

"This guy has just amazed us with what he's done," Bochy said. "Nothing surprises us with what he does and how he elevates his game and gets even better."

The Padres know just how the Diamondbacks felt.

Bumgarner has won both decisions against the Padres this season. In the last matchup which came in San Diego on May 17, Bumgarner notched a complete game by allowing a run on five hits while striking out 11.

Cashner takes the mound and the Padres take a deep breath.

Cashner is coming off a dreadful outing in which he surrendered eight runs and four home runs in Sunday's loss to the Los Angeles Dodgers. It was the second start back for Cashner after he missed most of June with a neck injury.

The inconsistent Cashner could also be feeling the pressure of scuffling in a season in which his contract expires.

"This year's been tough for him in the sense that he's got all the potential in the world," Padres manager Andy Green said to mlb.com. "It's just a matter of putting him in there, giving him the opportunity to show what he can do and hopefully move past those struggles."

The Giants have contributed to Cashner, who was once traded Chicago Cubs first baseman Anthony Rizzo, having a shoddy season.

They've beat him twice this year as he's lasted but 6 2/3 innings in his two starts. His 6.23 ERA against the Giants tells the story as Cashner continues to struggle with consistency, no matter the opponent.