Eli Manning has been handcuffed the past two weeks, posting quarterback ratings of 61.0 and 47.5 in losses to the New Orleans Saints and Arizona Cardinals, respectively. Four weeks ago, after being replaced by David Carr late in a 27-16 victory over the Kansas City Chiefs, Manning was diagnosed with plantar fasciitis in his right heel. The correlation between the signal-caller’s first rough patch of the season and his injury should be frightening for Giants fans.

The Big Blue Wrecking Crew rolled through its first five games of the year, and their fifth victory was a 44-7 rout of the Oakland Raiders, in which Manning completed eight of 10 passes for 173 yards and two touchdowns despite his ailing foot. Then again, the 28-year-old quarterback probably could’ve torched the Raiders’ secondary with his left arm.

But as the competition has gotten tougher — specifically, in the most recent contests against the Saints and Cardinals — Manning has started to falter, and the Giants have been suffered their first two losses of the season. After posting quarterback ratings over 100 in four straight games, Manning has completed just 49 percent of his passes the last two weeks, throwing only two touchdowns and four interceptions.

A tough road game in Philadelphia is next on the schedule, followed by a potential shootout in a matchup against Manning’s 2004 draftmate Philip Rivers and the San Diego Chargers. The Giants (5-2) are currently half a game ahead of the Eagles (4-2), but New York is in danger of dropping into second place if Manning doesn’t right his ship this Sunday.

Moreover, if Manning’s struggles are indeed related to the pain in his heel, they could become a lingering concern for an offense that has relied significantly on the air attack over the first half of the season.

Plantar fasciitis is an injury that requires a lengthy period of rest to go away, and it can recur at any time. Manning may be able to get better when the Giants reach their Week 10 bye, but the pain could come right back when he takes the field in Week 11 against the Atlanta Falcons. 

The Giants have one of the toughest schedules in the NFL from now through Week 14 — facing the Eagles twice, the aforementioned Chargers and Falcons, the undefeated Denver Broncos, and the Dallas Cowboys. If Manning isn’t at his best during that stretch, New York could easily tumble down the NFC East standings.