But the practice didn't help him on his first deep test: a bomb from quarterback Eli Manning that bounced off Nicks' face mask midway through the first quarter, turning what likely would have been a 54-yard touchdown reception into an incomplete pass.
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"I was wide open," Nicks said. "Eli threw the perfect pass. I would love to have it back. I can't control the sun. Wish I could've caught it."
The early letdown became a microcosm of some sloppy play by the Giants' receiving corps. The Giants' wideouts never looked in sync, dropping multiple passes. For the first time in five games, no Giants receiver reached 100 yards.
Manning did not throw a touchdown pass after three straight strong performances in which he had thrown at least two. His three interceptions also tied a season high.
But the receiving struggles were highlighted by Nicks, who was targeted 12 times and made only five catches. He also let a potential touchdown pass slip through his fingers in the fourth quarter.
His first-quarter gaffe, especially, seemed to haunt an overall forgettable afternoon for the Giants. Nicks said Manning and coach Tom Coughlin warned the receivers about the sun before the game. But he still fell victim to it.
"[The ball] was there, then it disappeared for a slight second," Nicks said. "Then when it came back, it was bad hand placement. My hands were lower than the ball. I reacted a little late."
It was the Giants' first 1 p.m. ET game since Nov. 13, but sunshine or not, Manning never seemed on the same page with his wideouts. He began 0-for-6, although one of the incompletions was the drop by Nicks. Manning blamed his fourth-quarter interception in the back of the end zone on miscommunication with Mario Manningham.
"I guess he went inside at the last second," Manning said. "It made it a little bit too easy of a play for the defensive back."
The Redskins have been one of the top pass defenses in the NFC, surrendering only 220 yards per game. Along with the three interceptions, they sacked Manning three times.
Although the Giants had some success with their running game -- they gained 34 yards on only five carries in the first half and finished with 91 yards on 18 carries -- they kept throwing, but the cohesion never seemed to get there.
Coughlin thought the northerly 9-mph wind could have played a role in that. Or the sun. Or some other reasons. But he challenged his receivers to execute better in supporting their quarterback in whatever circumstance.
"You need other people," Coughlin said. "You need to do some things when the ball is right there. Others have to rise up and play."