LOS ANGELES -- Over the last month, the Cubs had one of the best bullpens in baseball. Entering Friday night, Chicago relievers compiled a streak of 37 games without taking a losing decision.

That streak ended as the bullpen surrendered four decisive runs in the 6-2 loss to the Dodgers. It was an uncharacteristic outing from the National League’s most dominant bullpen, one that has compiled a sub-2.00 ERA since May 16.

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While the Dodgers have had their share of offensive struggles lately, Chicago’s relief arms assembled to keep the game within reach for the offense to come up with some run support. But pitches left in prime spots in the zone turned costly.

Before the bullpen gave up four runs late in the game, starter Jake Arrieta was responsible for the first two runs the Dodgers scored. The right-hander was in search of his first winning decision since late May and a bounce-back performance on the heels of his last start where he allowed six runs (four earned) in three innings to the Marlins.

Arrieta wielded his slider to record four strikeouts in his five innings against the Dodgers. He issued three walks and allowed five hits, with the runs coming in on a fielder’s choice off the bat of Gavin Lux and a home run by Zach McKinstry.

"They've gone through a skid lately, and they've been looking to get out of it,” Arrieta said. “We've played well, we've been up and down. I could have thrown the ball better, though. At the end of the day, I would have liked it to have been better for us.”

Arrieta has struggled with consistency on the mound. He’s in the midst of a stretch with four losses in his last six starts, leading to a lopsided 5-8 season record.

But manager David Ross believes Arrieta is showing signs of a resurgence. Ross noted that the veteran was locating his pitches when he needed to, all the while his arsenal maintained solid movement.

“I think all the starts are big, I don't put more importance on one than the other. I think he threw the ball pretty well,” Ross said. “The breaking stuff looked really good. He got beat on a couple of changeups, and just some misfires.”

Chicago jumped to the lead first with Kris Bryant’s 15th home run, crushed in the first inning on the first pitch he saw. Joc Pederson’s sacrifice fly in the seventh tied the game at 2. Southpaw Andrew Chafin replaced Keegan Thompson in the seventh by striking out Cody Bellinger and forcing Will Smith to fly out in the field.

But the script flipped in the eighth. Reliever Ryan Tepera, one of Thursday’s no-hitter heroes, opened the inning with a walk to Lux and paid the price when he left a sinker down and inside to AJ Pollock, who crushed the two-run go-ahead homer to left field.

With Chicago trailing by two runs, Ross called on right-hander Tommy Nance to try to prevent it from getting away from the Cubs. Nance foced Chris Taylor to ground out, but a sinker over the middle of the plate to Mookie Betts was driven to left field for a single. The damage continued when a four-seam fastball over the middle of the plate resulted in another two-run homer run, this time from Max Muncy.

The Cubs’ offense couldn’t compete with the long ball in the ninth against Kenley Jansen. The lack of run support led to Tepera taking the loss, making him the first Cubs reliever to be tagged with a losing decision since mid-May.