NEW YORK -- It just got a lot tougher to throw against the New York Jets.

A few hours before the NFL's free-agency period began, the Jets improved their secondary in a big way by agreeing in principle with the San Diego Chargers to acquire talented but troubled cornerback Antonio Cromartie on Thursday night.

The Jets confirmed the deal.

League sources told ESPN's Adam Schefter the Jets will give the Chargers a 2011 third-round draft pick that could turn into a second-round pick.

Cromartie has one year left on his contract and there are no plans for his deal to be redone now.

Cromartie was an All-Pro in 2007 and will team with Darrelle Revis in the Jets' secondary, making them possibly the best cornerback tandem in the NFL. Cromartie replaces Lito Sheppard, who was released earlier in the day after one disappointing season.

It could be a welcome change for Cromartie, who has struggled the last two seasons. He has 15 interceptions in four seasons since being the 19th overall pick out of Florida State in 2006, but the Chargers were dissatisfied with Cromartie's performance late last season and in the playoffs. General manager A.J. Smith made it clear he would try to trade him.