He can barely walk, but Patriots tight end Rob Gronkowski says his obliterated knee won't keep him from appearing in the upcoming "Entourage" movie.

TMZ Sports spoke with Gronk's entertainment manager Henry Penzi who tells us ... despite the fact he tore the MCL and ACL in his right knee last weekend, the NFL star is still excited for his big screen cameo. As we previously reported, Gronk will be playing himself in the flick.

We're told Gronk is scheduled to shoot his scene in February -- roughly 2-and-a-half months into his recovery. Usually, it takes about a year to heal from Gronk's injury (unless you're Adrian Peterson).

Gronkowski won't be the only guy on the "Entourage" set with medical problems -- Kevin Dillon's nursing a broken wrist and executive producer Mark Wahlberg has neck issues.