BEVERLY HILLS, Calif. — NBC's This Is Us isn't the kind of show that needs a big name to draw a crowd, but it's getting one anyway.

Sylvester Stallone — Philly's own Rocky — will guest-star in the coming season, the show's Penn grad creator, Dan Fogelman, said Thursday at the Television Critics Association's summer meetings.

"Sly Stallone is going to come and do a huge part on the show," playing a costar/father figure" to Kevin [Justin Hartley] in the film the character will be filming, Fogelman said.

Fogelman can thank This Is Us star Milo Ventimiglia, who plays Kevin's father, Jack, for helping to bring Stallone aboard. Ventimiglia played Rocky Balboa Jr. in the 2006 movie Rocky Balboa.

"Milo, obviously, knows him really well, and that was a big reason why I think he's doing it,"  Fogelman said. "We have a great script for him. I think it's going to be really, really exciting."