CLEVELAND -- For an entire season, Guardians closer Emmanuel Clase provided something that even the best relievers rarely can claim: near certainty.

But after two straight nights of struggles in the highest stakes games of the year, that certainty has been shaken.

On Friday, Clase gave up a pair of go-ahead runs to the Yankees in the ninth inning, absorbing the loss in New York's 8-6 win in Game 4, a defeat that pushed the Guardians to the brink of elimination in the American League Championship Series.

This came on the heels of a stunning Game 3, won by Cleveland in a wild finish that was set up by a rare Clase blown save. In that one, he gave up back-to-back homers to Aaron Judge and Giancarlo Stanton to lose the lead -- two homers in consecutive at-bats against a pitcher who gave up just two homers all season, posted a 0.61 ERA and converted 47 of 50 save opportunities.

"I just haven't been executing," Clase said after Friday's loss. "I'm failing against the hitters and I haven't had the results."

Uncertainty suddenly reigns around the game's premier closer, though the Guardians' support of their relief ace remains steadfast. Cleveland's deep and dominant bullpen has been the team's chief asset all season, but with Clase's October ERA now at 10.29 and other leaks springing throughout the bullpen, the group now has a 3.83 ERA, five losses and Thursday's blown save on its playoff dossier.

"We play a game based on failure," Guardians first baseman Josh Naylor said. "They've done such an incredible job for us. We believe in them and get excited every time they go to the mound."

Clase's struggles in Game 4 took a different shape than the home runs he allowed Thursday. This time, New York capitalized on three singles, a stolen base and an error to plate the go-ahead runs in the ninth. Unlike Game 3, when Clase's teammates rallied for a memorable win, this time the Guardians' late push fell short.

Asked if he has ever gone through such struggles, Clase said, "Not that I recall." He added that he appreciates his teammates' support and resilience.

"I have confidence in them," he said. "I told them thank you for the job they did."

Clase's quick departure after Game 3 raised some eyebrows, but he was at his locker, ready to field questions as soon as the Cleveland clubhouse opened Friday. The focus shifts to Saturday, and a Game 5 that the Guardians must win to keep their season alive.

"I'm not losing my confidence," Clase said. "I'm going to give my best. It's something that I'm surprised about, what's happening."