Ivan Nova stretches as he waits for manager Joe Girardi...

Ivan Nova stretches as he waits for manager Joe Girardi to take him out of the game in the 7th inning of a game at Yankee Stadium. (May 2, 2012) Credit: David Pokress

DETROIT -- The Yankees have struggled with runners on base for most of the season, but few think that's the team's biggest obstacle in winning the division or, at the very least, capturing a playoff spot.

"For me, with that lineup, I still think they're going to hit," an opposing team talent evaluator said. "If I'm the Yankees, the concern is my rotation. Do you really trust anyone besides CC Sabathia and maybe Andy Pettitte?"

To this point it's been a resounding no, the point brought emphatically home again in Wednesday night's 6-5 victory over the Angels that kept the Yankees from being swept.

Ivan Nova allowed at least five runs for the third time in his last four starts and the fifth in his last seven. Although the Yankees won five of those seven games, Nova has a 6.39 ERA and 1.65 WHIP in that stretch. He looks far removed from the pitcher who went 16-4 with a 3.70 ERA last season and somehow extended his winning streak to 15 games this year before the Orioles tagged him for five runs in 61/3 innings in a 5-0 loss at the Stadium.

Forget the 6-2 record. Nova has fluctuated between OK and awful, with Wednesday's performance sending his ERA to 5.60. That's just a little better than Phil Hughes (4-5, 5.64).

"I'm not pitching good," Nova said quietly after the game, repeating the sentence twice. "It's hard when you're not pitching good, especially when you know that you're better than what you're showing right now. It's been hard for me."

Nova's problems are emblematic of a staff that two months into the season hasn't gotten on a sustained roll, instead getting rolled with semi-regularity, often victimized by the long ball. Nova gave up one homer Wednesday, bringing the rotation's total to a major league-worst 54 in 50 games and 2982/3 innings.

Entering this weekend's series against the Tigers, the rotation's ERA is 4.82. Entering Thursday, only the Red Sox (5.06), Royals (5.18), Rockies (5.83) and Twins (6.19) were worse among the 30 major-league teams.

Given those awful numbers -- not to mention those of the Yankees' hitters with runners in scoring position (.223), with a runner on third with fewer than two outs (.214) and with the bases loaded (.151) -- the number that truly matters could be far worse.

Entering the three-game series here, which ends a nine-game, three-city trip, their 27-23 record doesn't look so bad.

"Would I like to be 40-and- whatever? Sure," Joe Girardi said. "But we're not and we have to keep trying to plug away . . . We're holding our own and just have to try to keep doing it."

The Yankees have done so in large part because of a bullpen that has a 2.69 ERA, third-best in the majors. It's been a remarkable performance, given that the unit lost its two best pitchers, Mariano Rivera and David Robertson, in a two-week stretch in early May.

But Rafael Soriano has gone 6-for-6 in save chances and Cory Wade and Boone Logan have provided a mostly stable bridge to him. Cody Eppley, Clay Rapada and David Phelps mostly have been OK.

Phelps has started two games and will be a candidate to start again if the Yankees decide they need to send Nova to Triple-A to work out his issues, which he theorized Wednesday are more "mental" than physical.

"I have to keep my head up and go back to work," Nova said. "I know at some point this year I'm going to start pitching better, and I hope it's going to be soon."

That's hardly reassuring.

As the calendar moves to June, hope rather than certainty seems to be the operative word for the Yankees regarding far too many of their starters.

No, I want to throw it!

Russell Martin had some harsh words for Laz Diaz after Wednesday night's game, saying the plate umpire all but baited him into trying to get himself ejected by not allowing him to throw fresh baseballs back to the pitcher after foul balls. "He told me I had to earn the privilege," Martin said, among other things.

MLB is looking into it. "We are constantly reviewing the interactions between player/umpire relations and will review this as well," an MLB spokesman said in an email Thursday.

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