PHOENIX -- When J.T. Thomas racked up 12 tackles and recovered a fumble in the end zone for a touchdown in the Jaguars' Week 13 victory over the New York Giants, he likely didn't realize the extent to which he was trying out.

"Thomas played very well against us," Giants coach Tom Coughlin recalled Wednesday. "And a lot of times, quite frankly, there's no better information as you get looking into free agency than people who've done well against you."

The Giants use a lot of advanced stats and rely heavily on their scouts when deciding which players to pursue in free agency, but they also do this thing Coughlin's talking about, where they kind of over-inflate a player's performance in a game against them when making their evaluation. Running back Rashad Jennings, who had 107 yards from scrimmage in a 2013 game against the Giants and signed a four-year contract with them last offseason, is a recent example.

So Thomas got a three-year, $10 million contract from the Giants on the first day of free agency this year, and Coughlin foresees a big role for him in the defense -- possibly as the starting weakside linebacker.

"We think Thomas could be a Will 'backer," Coughlin said. "[Fellow free-agent signee Jonathan] Casillas is basically the same kind of guy. Both are outstanding special-teamers. They'll make contributions in both ways. They'll both get plenty of opportunities. I just say that there's more information about Thomas in normal down-and-distance situations than Casillas."

Thomas played all three linebacker spots in Jacksonville and, as Coughlin intimated, has more experience on defense than Casillas has. So if you want to call him the favorite to start on the weak side, I'm not going to stop you. The Giants hope their linebacker lineup features a healthy Jon Beason in the middle with Thomas or Casillas on the weak side and some combination of Devon Kennard and Jameel McClain on the strong side. If Beason's healthy, McClain likely becomes a Swiss-army-knife backup at all three spots. If Beason once again struggles to see the field, either McClain or Kennard would play in the middle.

But assuming they can do what they want with Kennard, Coughlin also has some ideas about how new defensive coordinator can use him.

"A lot," Coughlin said. "If Jon comes back and Jon's healthy and Jon can play, then you've got Kennard maybe in a stronger position, rushing the passer more, the whole deal that way, and that's going to make you better."

Kennard had 4.5 sacks in the Giants' final five games and is hoping to build on a strong rookie season. Coughlin was asked if they might even be able to spot him in at defensive end if need be.

"You can. You can," Coughlin said. "That depends on who the other defensive ends are."

And that's a different blog post for a different time.