Welcome to the strangest week of the year in the NFL.

Half the locker room is focusing on what could very well be the biggest game of their lives, their last chance to catch the eye of a coach or scout, and make it onto an active roster on the back of a strong performance in the preseason finale. The other half, with roster spots secure, is frothing at the mouth and starting to look ahead to the regular-season opener in less than two weeks.

“There’s really no week in the NFL like this fourth preseason slash beginning of opening week,” veteran linebacker Jonathan Casillas said on Monday. “There’s nothing really like that at all, besides this time of the year.”

Casillas is among the group looking ahead to the Cowboys on Sept. 10.

“We’ve been thinking about them for a long time,” he said. “Everything’s been building for September 10. Whatever we’ve been doing come April, we’ve been building for September 10. All the preseason games were important, of course, but we’re all building for September 10. So, we’ve not just started with Dallas this week. We’ve been talking about Dallas, what they’re doing and how we think they’re going to attack us. We have been thinking about them a lot.”

As a former undrafted rookie, though, Casillas is also keenly aware of what the rest of the 90-man roster is feeling as it will soon be sliced almost in half. Teams must be at 53 by 4 p.m. on Saturday.

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“The worst day in the NFL is coming up, which is the cut day, and this year is different,” Casillas said. “We’re going from 90 to 53. It used to be in increments. I don’t know if we’re going to be prepared for that. There’s always some stuff that goes on, cuts happen where the days going on and someone gets pulled out of a meeting, just stuff like that. You hate to see it, it’s part of the game, and I’m not looking forward to it. At the end of the day, it is a business, and we do have to figure out the right 53 to play for the New York Giants. This fourth game is going to be very important.”

For some of the players, at least.