Model Lindsey Pelas -- Hollas At J.J. Watt ... 'Slide Into My DMs'

Sacks really do come easy for J.J. Watt ... 'cause the NFL superstar is getting straight up jocked by one of the hottest models on Instagram ... who's inviting him to "slide into my D.M.s."

The model calling out Watt is Lindsey Pelas -- who's already racked up more than 2 MILLION followers on Instagram ... and is basically the "it girl" on social media right now.

So, when we saw her at LAX Wednesday, we asked if there was a man in her life -- and that's when she invited the Houston Texans star to fill that gap.

Dude, do it.