Cardi B and Stefon Diggs drew a massive crowd for the Patriots receiver's holiday event at Gillette Stadium ... with the rapper going all-out in support of her man -- even doing some yoga poses in the process!!
The NFL star held a "Wellness Wonderland" women's function on Monday ... explaining, "I want to take some time to appreciate some hardworking women in the world and their little ones."
Stefon Diggs and Cardi B.