In three days, Howard Eisley has gone from third-string point guard to backup point guard, to getting the nod last night to start the second half against the Nets and helping lead the Knicks’ comeback from a 23-point deficit during a wild third quarter.

Is it possible for Eisley to wrest the starting position from Mark Jackson Sunday in L.A. vs. the Clippers? If he does, it’s by default.

Eisley and Jackson combined to shoot 6-of-17 in the Knicks’ 109-83 loss as the point-guard situation seems to be a mess.

Jackson, who said before the game the Nets’ record after seven games did not warrant them bragging rights just yet, was benched after offering up no defense on superstar Jason Kidd in the first half. Kidd had 12 assists in the half when the Nets built their 23-point lead.

In the defining moment of where these two franchises stand in terms of the all-important point guard position, Kidd swept down the right of the lane, blowing by the overmatched Jackson for an easy layup with 1:45 remaining in the second period to give the Nets a 21-point lead. The Meadowlands crowd rose to its feet in full roar as Jeff Van Gundy called time.

Of the benching, Jax said, “He made the call and you’ve got to suck it up.” Van Gundy afterward said hard decisions had to be made, so even Charlie Ward’s role could be revived.

With Eisley starting the second half along with Shandon Anderson replacing lifeless Allan Houston, the Knicks were revived and Van Gundy sent a giant message to his club that no one was safe. With Eisley running the show for the entire third period, the Knicks cut the deficit down to 73-71 with 58 seconds left in the third.

But the Nets pulled away from there.