Patriots DB Devin McCourty just threw some hilarious shade at the New England star ... saying Jules is now no longer the best-throwing wideout on the team!

And, why? McCourty tells TMZ Sports that honor belongs to his former Rutgers teammate Mohamed Sanu after New England just made the trade for him!!!

"I always tell Jules playing quarterback at Kent State is not much of an accomplishment," McCourty says, "because Sanu actually played quarterback my senior year in the Wildcat!"

If you're unfamiliar, Edelman has been the darling of Pats trick plays for years now ... using his college QB training to post a few passing TDs for New England since 2014.

But, McCourty says Edelman might have to compete with Sanu for future gadget plays ... 'cause he says the newly acquired WR has a stronger arm than even Tom Brady!!!

"If we need it, Josh McDaniels is always drawing something up," McCourty says. "I think Mo's QBR is really high, so, we can definitely use that in the offense."

FYI, McCourty ain't lying  ... Sanu -- who played with Devin for 1 year at Rutgers in 2009 -- has 7 career NFL completions for FOUR TDs on just EIGHT passing attempts!!

#BEAST

By the way, when McCourty, Edelman, Sanu and the Pats aren't just killing it on the field this season ... they're doing some huge things off of it.

Devin told us all about his upcoming charity Casino Night next week ... and explained to us why the cause he's supporting hits so close to home.

Seriously, it's awesome ... check it out!!!