EAST RUTHERFORD, N.J. – The preparations began for the Dallas Cowboys months ago. The New York Giants have been scouting the division rival they play on Sunday in their 2016 season opener since only a few days after the schedule was announced in April.

But the real preparations began earlier this week. The Giants turned their full attention to the Cowboys when they took the practice field on Monday, and the game plan was installed Wednesday.

Still, Thursday is perhaps the most important day.

“First day of pads with the 53[-man roster],” coach Ben McAdoo said. “It’s always a tough practice.”

The Giants were in shorts and shells (helmet and shoulder pads) on Wednesday as they prepared for rookie quarterback Dak Prescott, wide receiver Dez Bryant and the Cowboys. They’ll be in full pads Thursday as the intensity bubbles three days before the season opener at AT&T Stadium.

“Situational football. We’ll tax them between the ears and we’ll have the pads on,” McAdoo said of Thursday’s practice. “It’ll be physical.”

For a player such as newly signed offensive tackle Will Beatty, it’s an especially important day. Beatty will be tested for the first time since missing all of last season with arm and shoulder injuries. He joined the Giants last week after missing all of training camp and the entire preseason. Thursday should be a test to see how his body responds to banging against 250-plus-pound guys.

“Every day is a big day,” Beatty said. “It’s like the first day in full pads is not the first day in full pads since camp. It’s me in full pads for the first time in over a year. Just to put them back on and just to get that feeling.

“I was out there in the last preseason game in full pads, but I didn’t really get to hit anyone or use them. To break them in is going to be a good feeling.”

Things have changed around the Giants since Beatty last played. McAdoo is now the coach instead of the offensive coordinator, and the Giants have a completely new routine and schedule. Wednesday will be heavy on installing plays for that week’s game. Thursday will be testing it all out, mentally and physically.

That will be followed by what McAdoo calls “Fresh Friday.” The Giants will have a short practice where they will be challenged mentally more than physically. It’s a way to play the game before the game in their heads.

On Saturdays, the Giants will also take the field. They’ll have a “Launch Day.” They’ll practice for less than an hour at 80 percent or so to get everything functioning again, firing up the body to get ready for the game the following day.

It is a different routine than they had under Tom Coughlin for most of his 12-year tenure. The Friday-Saturday schedule was instituted just last year. The rest of the week (times, number of meetings, length of meetings) has been altered by McAdoo this offseason in an attempt to promote recovery and keep players healthier throughout the season.

The Giants entire 53-man roster was on the practice field on Wednesday. Only linebacker Jonathan Casillas and safety Darian Thompson were limited. Both are expected to play on Sunday against the Cowboys.

Even more eye-opening is that all 22 projected starters for the Giants from the start of training camp will play in the opener. They one of only a handful of teams that is so fortunate.