NFL

Jets’ safety-turned-corner Allen exits with likely concussion

If the Jets thought their cornerback situation couldn’t possibly get any worse, Friday night offered a cold dose of reality.

Converted safety Antonio Allen left in the first half with what was initially described as a head injury, leaving Gang Green even more shorthanded at that crucial position after a 35-24 preseason loss to the Giants at MetLife Stadium.

The situation was so dire, the Jets had undrafted journeyman LeQuan Lewis playing with the starters late in the second quarter, and Lewis was so bad it led to an actual touchdown by the Giants’ struggling first-team offense.

That would be the same LeQuan Lewis who, since 2011, has been on nine teams, including the CFL’s Toronto Argonauts.

Allen was only on the field at cornerback because the Jets’ two expected starters, Dee Milliner and Dimitri Patterson, are out indefinitely with injuries.

Allen’s injury — which looked a lot like a concussion — only adds to the long, difficult summer at that position for the Jets in general and general manager John Idzik in particular.

Idzik has been criticized for not signing a proven, reliable veteran in the offseason, despite more than $20 million room under the salary cap and former Jets star Darrelle Revis’ desire to return after being released by the Buccaneers.

Idzik also didn’t have to look far last night to see the veteran “name” corner who got away. The Jets had Dominique Rodgers-Cromartie in their building last spring, but couldn’t close the deal, and he signed with the Giants instead.

Allen was a temporary patch — having been moved to cornerback for the first time in his career two weeks ago after Milliner suffered a high ankle sprain and promising third-round pick Dexter McDougle was lost for the year to a knee injury.

Allen had a rough initiation last week against the Bengals’ A.J. Green, and he now might not see the field again for at least a week and perhaps longer. It will depend on the severity of the head injury he suffered while colliding helmets with teammate Demario Davis in the second quarter.

Darrin Walls, a backup pressed into a starting role by Patterson’s injury, managed to stay healthy Friday night, but struggled. He dropped a potential pick-six on a sideline throw by Eli Manning in the first quarter, then gave up a 26-yard completion to Rueben Randle on the next play.

Even the lone standout play all night by a Jets cornerback went for naught. Embattled nickel corner Kyle Wilson intercepted a Manning pass along the sideline just before halftime, but it was overturned because Wilson had stepped out of bounds before the grab.