SAN FRANCISCO -- Bruce Bochy insisted he wasn’t thinking about the possibility that Tuesday could mark Madison Bumgarner's final home start for the Giants.

"I haven’t even thought about it," Bochy said before the Giants rallied to defeat the Cubs, 5-4, in 13 innings on Pablo Sandoval’s walk-off home run at Oracle Park. "He’s saying the same thing. We’re doing a lot of good things right now. That’s all the team’s thinking about. That’s all Bum’s thinking about. It really doesn’t cross my mind. I don’t really have anything to say about it except, as always, I look forward to watching him pitch."

Others weren't as adept at pushing the thought out of their minds. One fan held up a sign that read, "THANKS BUM WE <3 YOU," and many of the fans in attendance made sure to send Bumgarner off to a loud standing ovation after he gave up three runs over seven innings.

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“Like I’ve said a million times, this is a special place to me,” Bumgarner said. “It always will be.”

Bumgarner departed with the Giants leading, 4-3, but he came away with a no-decision after the Cubs tied the game on Jason Heyward's RBI single in the eighth. Still, the Giants once again tapped into their resiliency and came back to win in the 13th inning after Sandoval drove a first-pitch fastball from Brad Brach to the opposite field for his 12th home run of the season and fifth career walk-off hit.

“I feel like everybody knew we were going to win,” Bumgarner said. “It was just, when is it going to happen? This is probably the best stretch I’ve ever been a part of.”

It marked the fourth walk-off victory in the last six days for the Giants, who have won 17 of their last 20 games to climb a season-high two games over .500 (52-50) and stay within two games of the National League Wild Card race. The last time San Francisco had a single-season stretch of 20 games with a 17-3 record or better was July 25-Aug. 16, 2001.

“We’re on a roll,” Sandoval said. “We try to do our best out there. We want to win games and go out there and fight every inning.”

The Giants' recent surge has likely decreased the possibility that Bumgarner will be moved ahead of the July 31 Trade Deadline, but it hasn’t eliminated it completely. No one knows what will happen over the next eight days, as the Giants’ front office, led by first-year president of baseball operations Farhan Zaidi, will have to weigh the benefits of keeping Bumgarner, an impending free agent, versus trading him for pieces that might position them better for the future.

The calculus is further complicated by Bumgarner’s status as franchise icon and World Series hero for the Giants, who selected him with the 10th overall pick of the 2007 Draft out of high school.

“He’s the face of this team,” Sandoval said. “He’s the greatest pitcher I’ve ever played [behind] on the field. He’s one of those guys you want to hand the ball to win games. He continues to do it in every start he has. He’s one of the greatest guys you want to have on your team as a pitcher.”

Bumgarner’s masterful track record in the postseason and return to peak form -- he’s logged a 2.00 ERA over his last six starts -- should make him attractive to several contenders, but the Giants could ultimately opt to keep him if they feel they aren’t receiving offers commensurate with Bumgarner’s value to the organization.

If the Giants hold on to Bumgarner, they could extend him a qualifying offer at the end of the season and receive draft-pick compensation if he departs as a free agent this winter. Despite the uncertainty surrounding his future with the Giants, Bochy said Bumgarner has remained unperturbed by the trade rumors, channeling the trademark focus that has fueled his past success in October.

“He’s looking to do all he can do to help us win,” Bochy said. “That’s all he’s thinking about. That’s all you can. Every year, you go through this. It’s never going to change when you get to this point. There will be rumors, especially where we were a month ago. Regardless, it’s not something you have any control over, and that’s what makes him so good. You’ve seen that focus and concentration in the postseason, you’ve seen in during the season. That’s what makes him so special.”