Flair is taking on NXT women's champion, Rhea Ripley, during the April 4 and 5 event at the WWE Performance Center in Orlando. It's one of the biggest matches of the event.

And, when Flair appeared on "TMZ Live" Friday, she told us straight-up -- "The pressure is on to deliver!"

Flair pointed out the fact there will be no live crowd at the event puts more of a focus on the wrestling performance -- and she knows she's gotta come through strong!

Also, since there's no other live sporting events due to the pandemic -- 'Mania could attract a record number of viewers.

"This might be the most-watched WrestleMania!"

There's more ... Flair also talked about Rob Gronkowski's involvement -- and while she respects the hell out of him, she's keeping it real about her in-ring expectations from the NFL superstar.

"I have a lot of respect for Gronk for what he's done with his athletic career but I always say this ... just because you're a talented athlete does not mean you're going to succeed in the ring."

"I'm so excited to have him as part of the team but I have no idea what his in-ring career will look like."

Earlier this week, we spoke with Charlotte's dad, Ric Flair, about Mania ... and yeah, HE'S FIRED UP! WOOOOOOOOOOOOOOOO!!!