FLORHAM PARK, N.J. -- After 15 games, Tony Sparano finally admitted that integrating Tim Tebow into the offense has been a hard fit.

One of the reasons why the Jets acquired Tebow was because of Sparano's background with the Wildcat; he used it as the Dolphins' head coach. But as Sparano correctly noted, the Wildcat is different from what Tebow ran last season with the Broncos. In Denver, it was a zone-read offense.

Of course, the Jets knew this when they traded for Tebow, but they went and did it anyway. And they raised expectations by hyping Tebow's prowess in the Wildcat.

"The Wildcat and what Tim did are really two different things," Sparano said Thursday.

Sparano said their Wildcat plays have been productive, but the zone-read players have been hit or miss. The problem, he said, is that it's hard for the players to get comfortable with the zone-read if it's not done on a consistent basis.

"And you really can't do that all the time right now with a player that's a part-time player," he said. "You can't afford to be able to do that all the time, and I think that's where maybe the lack of big plays come from, because you're not able to do it all the time."

So, basically, Tebow got caught in a Catch-22.

Statistically, he has hurt the offense. In 70 plays with Tebow on the field, the Jets have averaged 3.8 yards per play, 3.5 per rush and 5.1 per pass attempt -- and no touchdowns, according to ESPN Stats & Information. In 888 plays with Tebow off the field, they've averaged 4.7, 3.9, 6.4, respectively -- and 26 TDs.

Regarding the latest QB change, Mark Sanchez for the injured Greg McElroy, Sparano said it won't be a tough transition because of Sanchez's familiarity with the offense. Asked to describe his reaction when he heard McElroy couldn't play because of a likely concussion, Sparano said, "I was pretty silent."

NO CONTRACT TALK: Defensive coordinator Mike Pettine declined to discuss recent reports that he turned down a contract extension early in the season. But he said he'd like to remain with the Jets.

"I do," he said. "It's a great organization. I've enjoyed my time here. It's a great group of players. (I've been) treated very well. So, again, that's something that will take care of itself when the season is over."

SPECIAL K: Injured TE Dustin Keller (ankle) spoke to the media for the first time in weeks. This has been a rough year for Keller, who has played in only eight games -- in a contract year, no less. The team rebuffed his attempts to sign an extension before the season, so he'll be an unrestricted free agent unless they use the franchise tag.

"I just kind of put (the contract) on the backburner," he said. "I haven't really paid attention to that. I looked at it like, I'm not getting a new deal this year, so that's that, just go out and play."

Keller said he wants to remain with the Jets, but he's opposed to the franchise tag.