Beckham suffered a sprained ankle in the Giants' Aug. 21 preseason game against the Cleveland Browns.
The injury occurred on a hit by Browns cornerback Briean Boddy-Calhoun. Although OBJ appeared to be in significant pain, X-rays were negative, according to ESPN.com's Jordan Raanan.
Two days later, ESPN's Raanan and Dan Graziano reported Beckham missing "a week or two of the regular season" was a possibility.
Since entering the NFL as the No. 12 overall pick in the 2014 draft out of LSU, Beckham has been a fixture among the league's elite wideouts.
He has made the Pro Bowl in each of the past three seasons and has finished every campaign with at least 1,300 receiving yards and 10 touchdowns.
Last season, Beckham set a career high with 101 receptions to go along with 1,367 yards and 10 touchdowns for a Giants team that reached the playoffs.
He also played in all 16 games for the first time in his NFL career after missing four contests as a rookie and one in 2015.
Beckham was a huge contributing factor in the Giants beating the Cowboys twice last season, especially in their second meeting in December. OBJ caught a 61-yard touchdown in that game, which ended up being the difference in the 10-7 victory.
Quarterback Eli Manning will likely be forced to spread the ball around in Week 1 without Beckham in the fold. New York added some solid weapons during the offseason, as veteran wide receiver Brandon Marshall and rookie tight end Evan Engram will join Sterling Shepard to give the Giants a strong group of pass-catchers even without Beckham.