Beckham caught three touchdown passes and came within one reception of tying the team's single-game record. The Giants took advantage of an overturned touchdown at the end of the half to defeat Washington 24-13 Sunday.
Beckham and Eli Manning combined 12 times for 143 yards, with touchdown passes covering 10, 35 and 6 yards. He has a team-high nine touchdowns and his 972 yards receiving are a team record for a rookie, beating Jeremy Shockey's 894.
''I don't want to get his head too big right now, but he has a lot of skill,'' said Manning, who targeted Beckham 15 times. ''You hope he keeps working and grinding and doing the little things to correct. There is still room for improvement.''
That's scary. After missing the first four games of the season, Beckham has 71 catches, including 61 in his last seven games.
''As I said earlier in the year, there's no reason for this team not to have the best offense,'' Beckham said. ''The way we've played the last couple of games gives us a better feel for how we're going to play. For me, it's making the most of my opportunities.''
The win was the second straight for the Giants (5-9) after seven consecutive losses that eliminated them from playoff contention for the third straight season.
The Redskins (3-11) are finding all sorts of ways to lose, and this one was hard to believe. They blew a touchdown and command of the game on a fumble by Robert Griffin III as time expired at the end of the first half.
Griffin scrambled for an apparent 8-yard touchdown for a 17-7 lead, diving over the pylon, then running on to the field and spiking the ball with emphasis.
It wasn't to be.
The video review by referee Jeff Triplette showed that Griffin lost control of the ball diving over the pylon and the play was ruled a touchback.
''We shouldn't have let that play alter the game for us. Ultimately, it did,'' Griffin said. ''It's a touchdown. That's how we all felt, everybody in the locker room, coaches included. My understanding is, if the ball passes the plane and you have control of the ball, it's a touchdown in every game that I've ever seen. They decided that it wasn't today.''
The call incensed veteran Redskins receiver Santana Moss so much that he stormed after the officials and was ejected.
Triplette said Moss was ejected for inappropriate language directed first at him and then at field judge Alex Kemp.
Instead of a 10-point lead, the Redskins led 10-7 with the go-ahead points a 9-yard pass from Griffin to Chris Thompson midway through the second quarter.
New York, however, controlled most of the second half.
Moss was called for two 15-yard penalties and the Giants went with onside kick from the Washington 35 to start the second half. They recovered at the Redskins 17, setting up a tying 32-yard field goal by Josh Brown.
The 35-yard TD by Beckham gave the Giants a 17-13 lead late in third quarter. The 6-yarder with 4:41 to go sent the Redskins (3-11) to their sixth consecutive loss.
''This guy fuels the entire team, fuels the entire stadium,'' Giants defensive captain Antrel Rolle said of Beckham. ''He's an exciting guy to watch. He's a hell of a player. He goes out there and makes plays and plays beyond the X's and O's.''
Washington's only points in the second half came on a 38-yard field goal by Kai Forbath.
Manning (23 of 34 for 250 yards) drove the Giants 81 yards on four plays on the ensuing series, combining for the final 35 on a crossing pattern to Beckham. The rookie's catches were one shy of the Giants' single-game record held by Tiki Barber.
New York iced the game with a 76-yard drive that featured five catches by Beckham.
Griffin, benched for Colt McCoy as the starting quarterback, finished 18 of 27 for 236 yards. He also ran five times for 46 yards in an impressive performance, but was sacked seven times. There were moments late in the game when the oft-injured quarterback had trouble getting up.
''It's not been a fun year,'' Griffin said. ''We've had a lot of turmoil, a lot of things going on. At the end of the day, you suit up and when your number's called, be ready to play.''
McCoy led the Redskins to a field goal before leaving after aggravating a neck injury on the opening series.
Manning got New York on the scoreboard late in the first quarter with a 10-yarder to Beckham.
NOTES: This was the 100th NFL game at MetLife Stadium, the home of the Jets and Giants, which opened in 2010. ... Giants backup CB Chandler Fenner recovered the onside kick to start the second half. ... LB Perry Riley led Washington with 10 tackles. Fellow LB Ryan Kerrigan had Washington's only sack, his 12 1/2 of the season. ... Giants have 22 sacks in the last three games, with Jason Pierre-Paul and Johnathan Hankins each getting 2 1/2 Sunday.
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