Eli Manning is celebrating Tom Coughlin's 74th birthday by doing a pretty cool thing ... challenging a bunch of his ex-NY Giants teammates to donate to a cancer charity.
The former NY Giants head coach -- who led the G-Men to two Super Bowl titles -- also runs the Tom Coughlin Jay Fund Foundation, which raises money for family's affected by pediatric cancer.
Coughlin named the charity after one of his former players Jay McGillis, who played for Coughlin at Boston College.
McGillis was diagnosed with Leukemia in 1991, during Tom's first year as head coach.