He portrayed Dr. Greg Pratt on NBC's long-running medical drama ER from 2002 to 2008, and had a co-starring role opposite rapper Eminem in the 2002 feature film 8 Mile.

His character died during the conclusion of the season 14 finale cliffhanger involving an ambulance explosion that was rigged to kill an injured FBI informant (Steve Buscemi).

Phifer's television credits include the film The Tuskegee Airmen (1995), HBO's Subway Stories: Tales from the Underground (1997), and Brian's Song as former Chicago Bear Gale Sayers.

Phifer had a recurring guest role in the fifth and sixth seasons of Homicide: Life on the Street, portraying "Junior Bunk", the troubled nephew of Baltimore drug lord Luther Mahoney, and also guest-starred in New York Undercover.

[5] Among Phifer's other big-screen credits are Soul Food, The Biography of Spud Webb, Hell's Kitchen, NYC, Tears of a Clown, O (as the titular character Odin a.k.a.

He appeared in Impostor as well as Paid in Full, an urban classic, that has given him notorious recognition as he portrayed Mitch and director Curtis Hanson's 8 Mile, opposite Eminem.

[8] Phifer was the winner of the Celebrity Poker Showdown's fourth tournament, defeating Matthew Perry, Dennis Rodman, Kevin Nealon and Neil Patrick Harris in the Championship game.