With the San Francisco Giants continuing to struggle offensively, more pressure could be on Bumgarner the second time around.
The two left-handers match up again as the Giants visit the Washington Nationals on Tuesday night.
Both pitchers were impressive in Washington's 2-1, 10-inning road win May 22. Each allowed four hits and a run, with Gonzalez throwing 7 1-3 innings and Bumgarner seven.
Bumgarner has gone at least seven innings in his last 10 outings while posting a 1.77 ERA. However, he suffered a 6-1 defeat to Milwaukee on Wednesday after carrying a shutout into the eighth inning.
He yielded four runs - three earned - in giving up more than two earned runs for the first time in 11 games.
It was also the 11th time in Bumgarner's 23 starts that he received two or fewer runs of support.
"For whatever reason, we don't look like the same team we were last year," Bumgarner said. "There are things I could have done differently. There are things everyone could have done differently. It's been the same story all year."
The Giants (52-65) have lost six of nine while scoring 21 runs. They're batting .235 with 60 runs in 23 games since the All-Star break, the fewest in baseball.
Gonzalez (7-5, 3.52) has also been plagued by a lack of run support lately, getting backed with one run three times in his last four starts while losing the past two.
He yielded two runs over seven innings of a 2-1 defeat to Atlanta last Tuesday.
"I'm not worried about that (run support)," Gonzalez told the team's official website. "My job is to go out there and pitch, keep these guys in the game."
The Nationals (57-60) have shown signs of life recently, following a four-game losing streak with a three-game home sweep of Philadelphia. They outscored the Phillies 23-7 and recorded at least 11 hits in each contest.
Bryce Harper is 3 for 9 off Bumgarner with a home run earlier this year.
The Nationals have won five straight meetings in Washington.