Yanks’ rotation concerns Girardi

The Yankees have about a month to reinvent their wobbly starting rotation, which isn’t exactly how they envisioned their final sprint to the playoffs. Unless you consider Ivan Nova a realistic option for October, the Bombers are down to one weapon, CC Sabathia, and a million reasons to worry.

That good news is that the big lefthander seems up to the challenge: He never seems to lose in the second half. Although Sabathia was less than brilliant in a 12-9 victory over the White Sox on Saturday, he nevertheless picked up his 18th victory and ran his career record in August to 38-10. That’s a .792 winning percentage, good enough for the Yankees to hang their hat on.

That is, if Sabathia could pitch every day. As it is, he’s under enormous pressure to win all six of his remaining starts while Joe Girardi scrambles to find a workable calculus. Does he dare trust A.J. Burnett? Will Andy Pettitte return from the disabled list in time to be sharp for the division series? Can the remainder of Phil Hughes’ 175 innings be properly finessed before he reaches his organization-imposed threshold?

These aren’t just idle curiosities for a team floating towards the postseason. The Yankees are in a street fight with the Rays that just might go down to Games 160, 161 and 162 in Fenway Park, ironically enough. And while it might not quite feel like a 1978-type win-or-else weekend, the Yankees are no less anxious about it, especially as their pitching continues to flounder.

Since the All-Star break, the Yankees are only eighth in the American League in ERA, down from their No. 2 ranking in the first half. Losing Pettitte has crippled them, as has the concurrent unraveling of Burnett and Javier Vazquez. The combination of injury and under-performance turned August into a .500 (13-13) month for the Yankees, which is why they ended a Toronto-Chicago road trip in a dead heat with the Rays.

Although it seemed like the Bombers were running in place, Girardi was busy making executive decisions on Vazquez (demotion to long relief) and Burnett (public warning of a similar punishment). The manager rarely criticizes his players in front of the media, but he all but advertised Burnett’s days in the rotation were numbered after a horrific performance against the White Sox Friday night.

Burnett confessed it was “unacceptable” to have allowed eight earned runs in 3.1 innings. With a 5.17 ERA and 1.51 WHIP, he’s becoming a perfect storm of errant fastballs through the heart of the strike zone and curveballs that bounce in the dirt.

That’s a universe apart from what the Yankees thought they were getting from Burnett two years ago as a prize free agent. Back then, he featured a high-90s four-seamer and a curveball that could buckle hitters because it broke so late and so violently.

At some point since 2009, however, Burnett has lost the feel for, or perhaps the ability to get swings and misses with, his curveball. That sharp break has softened into a lazy roll. Sensing its deficiency, Burnett lately has tried to speed up the curveball by accelerating his arm — only to drop the pitch uselessly in front of the plate.

Watching him now, it’s hard to remember that Burnett was once so unhittable. With the Marlins in 2005, his secondary stuff was pure poison, as the National League made contact with only 36 percent of pitches out of the strike zone. No one, it seemed, could square up on his sinkers and monster curves.

This year, however, with far less mystery to his stuff, Burnett has run into the highest contact ratios of his career: 63 percent out of the strike zone, and 90 percent overall.

Burnett says all this still can be fixed in September, but Girardi never has seemed less convinced. The problem is, without Pettitte and with long men Chad Gaudin, Sergio Mitre and Vazquez as his only other options to replace Burnett, the manager’s hands seem tied.

The Yankees’ best hope is for Nova, the rookie, to be to this year’s team what Mel Stottlemyre was in 1964, going 9-3 after being called up in mid-August.

Stottlemyre helped take the Bombers to the World Series, which at least creates a precedent for a late addition, even a first-timer, to act as the missing spark.

But the Yankees don’t dare think of October just yet, not with critical end of September series with the Rays and Red Sox. By then Girardi will know if Burnett can ever be trusted and, even more critically, if Pettitte can clone his first-half success.

Without them, the Yankees go into the stretch run with an elite-caliber offense, a lock-down closer and an ace on a historic roll. Most other teams would die for those weapons, but the question is whether the Yankees, in their current state, have enough to hold off the Rays.

The Bombers still think so. But these are the sort of uncomfortable questions they never thought they’d be wrestling with, at least not this late in the season. The Yankees’ flaws might be making their fans squirm, but consider the other prism: It’s going to be a fire-breathing finish.