MILWAUKEE -- The remnants of the 98.3 mph liner that struck Madison Bumgarner on his pitching arm remain visible in the form of some residual bruising around his left elbow. Bumgarner admitted he’s not completely past the left elbow contusion he suffered a week ago, but he found a way to keep the Brewers at bay Saturday night.

Bumgarner allowed only an unearned run and struck out six over five innings, but he did not factor into the decision as the Brewers rallied to beat the Giants, 5-4, on Ben Gamel’s walk-off double off Reyes Moronta in the ninth inning.

The Giants scored twice in the top of the ninth to tie the game at 4 on an RBI single by former Brewer Stephen Vogt and an error by center fielder Lorenzo Cain, but the Brewers quickly responded in the bottom half of the inning. After Ryan Braun reached on an error by shortstop Brandon Crawford, Moronta issued a two-out walk to Keston Hiura to bring up Gamel, who ripped a double to right field to end the game.

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“A hard-fought game,” manager Bruce Bochy said. “I loved the way they just kept battling and almost pulled it out.”

The Brewers made Bumgarner work hard, forcing him to throw 103 pitches after fouling off 24 of his offerings, but they were blanked through the first four innings before breaking through in the fifth.

After striking out Tyler Saladino, Bumgarner misplaced a 1-1 fastball to Brewers right-hander Zach Davies, who drove it to left field for a double. Bumgarner retired Lorenzo Cain on a flyout before Christian Yelich hit a potential inning-ending grounder that second baseman Joe Panik couldn’t handle, allowing Davies to score and tying the game at 1.

“It’s not completely normal yet, but it was good enough,” Bumgarner said of his bruised left arm. “No pain. It feels normal. There’s still some swelling in there and some bruising. ... It was definitely a grind. I had to pitch through a lot of traffic, a lot more than you’d want.”

Despite Panik’s untimely error, Bumgarner also benefited from a pair of outstanding defensive plays from catcher Buster Posey, who threw out Cain at third base to end the first inning before helping the Giants execute a key 8-6-2 relay to nab Mike Moustakas at the plate in the fourth.

Moustakas singled and attempted to score from first on a two-out double by Manny Pina, but center fielder Kevin Pillar quickly played the ball off the wall and threw to Crawford, who delivered a one-hop throw to Posey at the plate. Posey received the throw and made a lunging tag to get Moustakas before his hand touched the plate.

“That play at home, there’s not a more difficult play for a catcher,” Bochy said. “An in-between hop, a great tag he made to save a run there.”

Bumgarner has now allowed just four earned runs over 20 innings (1.80 ERA) in his last four starts, lowering his overall ERA to 3.86 on the season. That impressive stretch began after the 29-year-old veteran made an adjustment following a rough start against the Dodgers on June 20, when he gave up six runs over a season-low 3 2/3 innings. Bumgarner realized he had become too predictable to one side of the plate, so he began moving the ball around to a greater extent.

Bumgarner’s surge should catch the eye of contending teams looking to bolster their rotations ahead of the July 31 Trade Deadline. The Brewers, who will be searching for pitching help in the coming weeks, are among the teams who have been linked to Bumgarner, and on Saturday, he provided an up-close glimpse at what he has to offer.

“He was pitching without his best stuff there, but he found a way,” Bochy said.