The wideout was attempting to make a catch when he was hit by Washington's Deshazor Everett. Board was motionless on the field after the play.
Medical personnel brought him off the field after removing his face mask and stabilizing his neck.
He was ruled out for the remainder of the game. According to Dan Salomone of the Giants official website, Board was diagnosed with a concussion and strained neck and is being evaluated at a hospital.
After the game, head coach Joe Judge revealed he had received "pretty positive" feedback regarding Board's condition.
"That was a relief," Judge said after his team's 20-19 victory over Washington, per ESPN's Jordan Raanan. "The one thing I can say, good-news-wise, is that even on the field, he was moving, he was conscious, he was responding. He had movement in all his extremities. They obviously had to have some precautions with what they were doing."
Board had one catch for eight yards on three targets before the injury. He entered the day with six catches for 58 yards on the season.
The 26-year-old has bounced around the league over the past few years, initially being signed by the Baltimore Ravens in 2017 as an undrafted free agent out of Chattanooga. He spent time on practice squads before making his regular-season debut with the Jacksonville Jaguars last season, totaling two catches for 31 yards in 2019.
After being waived by Jacksonville in August, the Giants claimed Board and provided him his best opportunity for playing time with the team dealing with injuries at the position.
With Sterling Shepard also out, New York has limited depth at the position behind Darius Slayton and Golden Tate.