Eli Manning Still Plays 'Pivotal Role' On Giants, Says WR Darius Slayton

Eli Manning ain't the Giants starting QB anymore ... but he's still one of the team's leaders, so says NYG WR Darius Slayton, who tells TMZ Sports the future HOFer is a critical member of the squad.

Slayton -- a rookie out of Auburn who was taken in the 5th round of this years NFL Draft -- played in his 1st NFL game Sunday ... catching 3 balls for 82 yards (he also made a critical block on Evan Engrams 75 yard TD reception).

We talked to Darius earlier this week ... and he told us even though it's Daniel Jones receiving the adulation, Eli's been a great teammate and a big presence in the locker room.

"I think he's been a real pro. Honestly, from the day they announced it until now, he's been the same guy. He's came in, I think he's really tried to help [Daniel Jones] get ready week in, week out because obviously you can't replace 16 years of experience," Slayton told us.

"There's no way we can learn everything he knows in a matter of months. He still plays a pivotal role in this team and it's a blessing to have a guy like that around."

Darius -- who's only been around the Giants organization for a few months -- says Eli might not be under center anymore on Sundays, but he's still a valuable piece of the NYG ... and someone whose contributions to New York will be remembered long after Manning hangs up his cleats.

"He's still a big leader around here. He's still Eli Manning now. He's got rings, he's all over the facility. It's really important for a guy like that to be involved and be part of the team. I don't think he'll be forgotten around here anytime soon."