Per New York's official website, he did not make the trip to the nation's capital with the team.
Beckham was listed on the injury report as a limited participant in Friday's practice.
It's just the latest injury for the New York star. He was limited to just four games last season after fracturing his ankle in October. The former first-round pick has played in 16 games just once through his first four seasons, as he played in every regular-season and postseason game in 2016.
Beckham was fully recovered and good to go when Week 1 arrived. He has 77 catches for 1,052 yards and six touchdowns in 2018.
"Like I said, it's not a down year. My numbers are still my numbers," Beckham pointed out in late November, per ESPN.com's Jordan Raanan. "I guess that is where my mindset is different than everybody else. I expect way higher of myself."
When healthy, there is little doubt the 26-year-old is among the best wideouts in the NFL. He and Eli Manning have formed one of the best connections in the league. The 5'11", 198-pound receiver recorded at least 90 catches, 1,300 yards and 10 touchdowns in each of his first three seasons.
That historic start to his career helped him land a five-year, $95 million extension this past offseason.
It hasn't been the smoothest of seasons for Beckham and the Giants, even with the record-setting extension taken care of. The star wideout caused a stir when he told ESPN's Josina Anderson that his team lacked heart during a 1-3 start and that it was a "tough question" as to whether he was unhappy in the Big Apple.
It certainly didn't help matters that he also questioned the team's (and Eli Manning's) inability to throw the ball down the field.
This season has weighed on Beckham.
"You can go home with 300 yards in a game with an L—it's not going to feel good," Beckham told Raanan. "So it's really all about winning, and I just feel like I could've had a better year so far but this is where I'm at. You just have to deal with that, keep pushing to keep getting better day by day, work at your craft. That is all I can really do."
With Beckham out, the Giants (4-8) will have an even tougher time winning games as the offense will be without one of its top playmakers.