PHILADELPHIA -- Manager Rick Renteria is the first to acknowledge that the past few weeks have not gone the way the White Sox were hoping.

His club is just 6-17 since the All-Star break, including 3-8 in its last 11 games. Believe it or not, however, there have been some bright spots during this "tough run" -- and that's not just manager speak.

Take, for instance, the bullpen -- specifically left-hander Aaron Bummer.

The White Sox relief corps have a 2.33 ERA since July 18 That's by far the best mark in the Majors during that span, and a far cry from the bullpen's 4.66 ERA prior to that point. No reliever has been better than Bummer, who pitched another 1 2/3 perfect frames in Sunday's 10-5 win to lower his season ERA to 1.69.

"I think the entire bullpen, top to bottom, has been throwing the ball extremely well over the last couple weeks and it’s given us a chance later in games to at least stay in those games," the 25-year-old said before Sunday's game. "We’re definitely feeding off each other. Everyone’s throwing the ball really well, and we’re pulling for each other."

Bummer had held the opposition scoreless in eight of his nine appearances during the team's rough stretch since the All-Star break. Strangely enough, it was the one outing in which he did allow a run that ultimately proved to be one of his more impressive performances of the season.

Entering to pitch the seventh inning of Friday's eventual 15-inning victory with the game knotted at 2, Bummer allowed a one-out bunt single followed by an infield hit to put runners at the corners. After a high chopper found its way through the right side of a drawn-in infield to plate a run, the White Sox intentionally walked Rhys Hoskins to load the bases with one out for Bryce Harper. Bummer struck out the Phillies slugger on four pitches, then followed with another strikeout of J.T. Realmuto to end the threat.

"I’d really like to keep them scoreless every time I go out there -- I think everybody wishes and hopes that they can do that," Bummer said. "But in years past, I think I might let an inning like that get a little sideways. This year, I’ve kind of been able to work through that and get those last couple outs to minimize damage."

While Bummer relied on a couple key strikeouts in that instance, it's been his ability to limit hard contact that has helped him turn the corner in 2019. Of the 105 balls put in play against Bummer this season, only two have qualified as barrels, according to Statcast. That barrel percentage of just 1.2 percent ranked best among 326 big league pitchers to allow at least 100 batted balls this season.

The lack of hard contact has allowed Bummer to hold opponents to a .172 average, well below the .301 mark he yielded last year en route to posting a 4.26 ERA.

"He’s attacking the strike zone, and he’s got a lot of action on his pitches," Renteria said. "I think he’s continued to breed more and more confidence. He did a lot of work and continues to be impressive."

Unfortunately for Bummer and the rest of the bullpen, this impressive stretch has overlapped with the offense going cold. While dealing with injuries to Yoán Moncada, Tim Anderson and Eloy Jiménez, the White Sox entered Sunday averaging just 2.8 runs per game since the All-Star break. That's more than half a run worse than any other big league team during that span.

"Some of these games we’ve been in late, where a timely at-bat here or there maybe puts us over the top and gives us an opportunity to win a ballgame," Renteria said. "We haven’t had those as much, obviously, in the last 15-16 days. It’s still there. It’s still in these guys. They’ll be fine, they’ll settle back down."