MLB

Is the Yankees bullpen running out of steam?

ARLINGTON, Texas — Was it a one-night stand that turned into a nightmare and skewed the math? Or was it a continuation of a recent trend by the Yankees’ biggest strength?

Across almost four months of a season in which the starting rotation was decimated by serious injuries and the lineup failed to produce consistently, the Yankees stayed in touch with the AL East leaders thanks to a bullpen led by Dellin Betances and David Robertson.

Tuesday night they, and Adam Warren, combined to turn a laugher into a white-knuckle 12-11 victory over the Rangers at Globe Life Park.

The numbers, admittedly a small sample in the games since the All-Star break, indicate a downward trend by Betances and Robertson, two arms the Yankees are going to need to cut into the 4 ½-game deficit they were working with in the AL East.

Before the All-Star break, Betances appeared in 42.5 percent (40-of-94) of the Yankees’ games. Going into Wednesday night’s game, one he was doubtful to pitch in since he threw 25 pitches Tuesday, Betances had appeared in seven of 12 games (58.3 percent). His WHIP went from 0.705 to 1.200, the ERA from 1.46 to 2.16, batting average against from .124 to .214 and K’s per nine innings from 13.7 to 11.9. The K-to-walk ratio went from 5.25 to 2.75.

Dellin BetancesPaul J. Bereswill

“I feel good, I am doing my same program,’’ said Betances, who gave up a grand slam to J.P. Arencibia Tuesday after inheriting three runners from Warren in the seventh. “On the days I pitch I do my five-part shoulder program. I feel good.’’

In his first year as a big league reliever Betances, an All-Star, had appeared in 47 games and pitched 63 ²/₃ innings.

Robertson, who has done a splendid job of replacing Mariano Rivera (converting 27-of-29 save chances), had a numbers dip, too.

Prior to the break, Robertson worked 34 percent (32-of-94) of the games; since then it had been 58.3 percent (seven of 12). The ERA had jumped from 2.76 to 3.38 and the Ks per nine innings had dropped from 16.3 to 10.1 as had the K/walk ratio from 5.90 to 2.25.

“We had a bad day, an off night,’’ Robertson said of Tuesday night’s debacle in which allowed he two hits, two runs and walked three in a ninth that ended when Adrian Beltre flied to deep left with the bases loaded.

Robertson was credited with the save.

“Give them one hiccup,’’ Mark Teixeira said of the bullpen. “We haven’t been picking them up. They have picked us up all year.’’

Joe Girardi’s biggest plus as a manager is handling the bullpen to make sure he doesn’t wear out the arms.

“I do a little bit and I will have to watch them as we go down the stretch. The good thing is that we have an off day Thursday and the guys who don’t pitch [Wednesday] will get two days off and it will probably refresh them a bit,’’ Girardi said. “They have been used but they have been pretty good, too. It’s one of those nights, but they have been pretty good, too. I don’t worry about our bullpen, our bullpen is going to be good down the stretch. They just had a [bad] night, everyone is entitled to one night. We were tired of giving you 4-2 games.’’

Girardi isn’t stressing that Betances’ brutal Tuesday was a warning sign.

“I wouldn’t make too much out of it. He gave up the home run and then he did what he did. He struck out a couple of guys. I am not going to make too much of it,’’ Girardi said.