AN ACE...AND THEN HOLES

Yanks need more than Severino on hill

Luis Severino keeps pitching like a bonafide ace. It’s everyone else in the Yankees’ rotation that’s a concern. After Severino’s latest gem versus Houston on Wednesday, in his two starts against the Astros this season, he’s posted a 1.13 ERA, with 21 strikeouts in 16 innings.

Last year, Severino had a 10.57 ERA against Houston in the regular season and a 4.15 ERA in the playoffs — failing to get through the fifth inning in either of his ALCS outings (one due to precautionary reasons). The Bombers are 11-1 in Severino’s starts this season. And since a clunker in Boston on April 10, Severino is 6-0 with a 1.95 ERA.

But staring pitching beyond Severino remains a problem.

Masahiro Tanaka and Sonny Gray have been the main culprits. Tanaka has a 4.62 ERA with 12 homers allowed, while Gray, who will start Friday against the Orioles after Thursday’s game was postponed due to rain, has a 5.98 ERA. Granted, Baltimore has been shut out in two of its last three games.

“Sometimes Tanaka looks like a No. 1, other times he looks like a No. 5,” said one scout. “But I trust him a lot more than I trust Gray in a playoff game.”

CC Sabathia hasn’t pitched well in his last four starts (7.85 ERA) — though he’s also 37 — whereas Tanaka and Gray are still in their pitching primes, so to speak. And Jordan Montgomery is still far away from returning off the disabled list, having yet to throw off a mound.

Tanaka has yet to complete seven innings in any of his 11 starts, while Gray hasn’t completed five innings in five of his 10 starts.

The result has been a more taxed bullpen — and the constant need for a 13th pitcher.

“Look, as good as we think our bullpen is, ultimately it’s the starters that can help make that bullpen even stronger by protecting them and not having to overuse them, and you do that by getting deeper into games,” Aaron Boone said. “Hopefully we’ll start to get a little more deep into games with guys other than just Sevy.”

A starting pitching upgrade is obviously on the Yankees’ to-do list before the trade deadline, but the market is still just taking shape.

Texas lefty Cole Hamels could be a possibility — for a lesser prospect return and if the Rangers eat a portion of his remaining $22.5 million salary, which could be tough for the Yankees to fit under the $197 million luxury-tax threshold.

Michael Fulmer, an offseason target, has a 4.60 ERA — not exactly enticing at this point.

Many fans would like Madison Bumgarner, who could make his season debut on Tuesday. But the Giants brought in veterans Evan Longoria and Andrew McCutchen in the offseason, so they don’t seem like a team that wants to be in sell mode — despite being 26-30.

It would be surprising if an AL East rival like Toronto (J.A. Happ) or Tampa (Chris Archer) would do a deal with the Bombers for a starter. Maybe Arizona will continue to flounder, opening the door for the Yankees to make a run at free-agentto-be Patrick Corbin. Meanwhile, Tyson Ross has a 3.29 ERA in San Diego. he Bombers certainly have enticing pieces like Clint Frazier and Chance Adams with which to potentially

moves. Whatever the case, it can’t just be Luis Severino and little else.

“It’s tough to keep winning by scoring six or seven runs a game,” the scout said.

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