Teams can start negotiating with the agents for other teams' free agents as of noon Monday, though no agreements can be made official until 4 pm ET on Wednesday. With nearly $60 million in cap space and a ton of needs on the defensive side of the ball, the New York Giants are expected to be active early in the free-agency period.

The Giants already have had free-agent defensive end Charles Johnson in for a visit and have expressed interest in free-agent defensive end Mario Williams. Those two players are eligible to sign at any time because they were cut before their contracts expired. The Giants also have had discussions with their own free-agent defensive ends, Jason Pierre-Paul and Robert Ayers, whom they could sign at any time as well.

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But while the Giants will continue to be active in the hunt for edge-rush help, checking in on everyone from Olivier Vernon to Adrian Clayborn to Williams Hayes to the prospects they can take with the No. 10 pick in the draft, they'll also be in the hunt for help on the interior of the defensive line, where some stars are available.

Denver's Malik Jackson is the name everyone wants to know about, and the Giants have some interest there. But don't be surprised if the more likely defensive tackle is someone who played a lot closer to East Rutherford. Damon Harrison, the 27-year-old nose tackle who's spent the past four years with the Jets, is expected to hit the market and should be of interest to the Giants. He's a 6-foot-4, 350-pound run-stopper who'd look really good next to Johnathan Hankins on the defensive line between whoever the ends turn out to be.

Last year in free agency, the Giants missed out on some of their top defensive tackle targets, including Dan Williams, and ended up signing Harrison's former backup, Kenrick Ellis. That didn't work out, and while Cullen Jenkins could still re-sign and Jay Bromley could be ready for a larger role, Harrison is one of the best interior run defenders in the entire league and would shore things up dramatically on first and second downs.

You're going to hear a lot of names connected with the Giants in the coming days, and they'll be in on more or less all of the big defensive free agents to some degree. But Harrison is a name to watch, and he'd be a smart signing for the Giants as they try to rebuild their defense for the long term.