In the moments when Washington Redskins players weren’t scurrying from one drill to another in Monday’s joint practice with the New England Patriots, quarterback Tom Brady reminded Robert Griffin III that he’s been running the same offense for nearly 15 years.

And Griffin, he pointed out, is still new to the NFL.

“He said this is only my third year, and I have a lot of football left in me,” Griffin said, recounting his chat with the future Hall of Famer. “That’s big coming from a guy like him.”

Brady’s words provided solace on a day that highlighted the sizeable gap in efficiency between the Patriots and Redskins. But it won’t amount to any points when the teams square off at FedEx Field in Thursday’s preseason opener.

Nonetheless, Griffin struck an upbeat tone afterward.

The Post Sports Live crew explains why no major news out of training camp is good for the Redskins coming off of a 3-13 season. (Post Sports Live/The Washington Post)

“Everybody came out here obviously ready to go,” said Griffin, who completed several nice throws but would have been sacked at least two or three times Monday had full contact been allowed. “We showed that we are a physical football team. We ran the ball extremely well, and I thought we pass protected pretty good, as well.”

The joint practice marked a return to the preseasons of old for the Redskins, when the squad, under former coaches George Allen, Joe Gibbs, Norv Turner and others, scrimmaged against Pittsburgh, Tampa Bay and the former Houston Oilers midway through camp to break the tedium.

The idea of resurrecting it started with a three-way phone conversation among Patriots Coach Bill Belichick, Redskins Coach Jay Gruden and Washington President and General Manager Bruce Allen once the preseason schedule was set. The coaches roughed out the script and fine-tuned it as Monday approached.

Against a Patriots team that finished 12-4 last season, some Redskins players seized the chance to shine. Wide receiver Aldrick Robinson ran a great corner route to grab a deep ball thrown by Kirk Cousins. Keenan Robinson ably filled the defensive signal-calling vacancy left by London Fletcher. Running back Alfred Morris revved up his motor behind solid run-blocking by the offensive line.

But the physical play of New England’s cornerbacks, particularly Darrelle Revis, knocked the Redskins’ younger receivers around a bit. And Griffin must do better with his decision-making, Gruden acknowledged.

“Robert’s only in his third year, and this is his first in this system, so there will be some growing pains,” Gruden said. “But ideally I want him to have just total understanding of every possible play and every coverage scenario and where to go with the football. And it’ll come for him. It’ll take some time for him, but it’ll come.”

The Patriots’ hurry-up offense was also a handful for the Redskins’ defense.

“Everybody knows that Tom is one of the best quarterbacks that’s playing this game,” said Redskins cornerback David Amerson. “He’s commanding their offense pretty good. The hurry-up is pretty efficient and real fast — something you’ve got to adjust to.”

But the first of three joint practices was an unqualified victory for fans of both teams, who reveled in the chance to see Griffin and Brady up close and cheer the day’s big catches and hard hits. The Redskins said 21,047 fans were in attendance.

The Patriots faithful were first to mass at the entrance to the Redskins’ Richmond training camp, with Jennifer Sastre, 27, of Fort Bragg, N.C., staking out her spot at 1 a.m.

“They’re all the way in Foxborough, so when they’re close, you have to take the opportunity to go see them,” said Sastre, who carried a hand-lettered poster that read, “I drove 948.6 miles to meet BRADY!”

She led the sprint to the sideline at 7:30 a.m., with thousands of Redskins and Patriots fans behind, toting folding chairs, blankets, banners, binoculars and cameras.

The complex, purpose-built for the Redskins, features two adjacent full-sized grass fields and a smaller one for specialized work. By 8 a.m. fans were jammed shoulder-to-shoulder, eight- or nine-deep, along one sideline, crammed on a hillside above and crowded behind an end zone.

One family held up a sign in both teams’ colors that proclaimed: “We are a House Divided! But we all agree: Redskins and Patriots Rule, Cowboys Drool!”

The teams trotted out at roughly 8:30 a.m. and launched into stretching on separate fields. That was followed by joint work on kickoffs.

Position drills followed. Patriots quarterbacks threw to wide receivers, while Redskins quarterbacks handed off to backs and linemen polished footwork.

With 180 players arrayed on separate fields, it was dizzying to follow the action, which was chronicled by video cameras perched atop five cranes.

Then came running and passing drills. While most fixated on quarterback play, former Redskins linebacker Ken Harvey planted himself behind an end zone to study the battle between the Redskins’ offensive line and Patriots’ defensive line.

“That’s to me one of the most important things you want to see,” Harvey said. “Looks like they did pretty good.”

There were two 11-on-11 sessions in which the Redskins offense took on the Patriots defense, while the Patriots offense squared off with the Redskins defense.

Griffin handed off to Morris for a big gain up the left side for a feel-good start to one sequence. Roy Helu Jr. gained ground up the middle on a subsequent play. But Griffin overthrew a wobbly deep ball to DeSean Jackson. As the day unfolded, the quarterback fared far better on short throws to Santana Moss and tight end Jordan Reed.

Whether it was Brady’s quickness in getting rid of the ball or a lag in recognition and speed among the Redskins’ secondary, the Patriots quarterback fired a succession of completions to wide-open receivers.

“We got a little ways to go,” said Redskins cornerback DeAngelo Hall, “but you want to use this as a measuring stick.”