Panfil shares the award with New Mexico cornerback Glover Quin.
A senior from North Crowley High School in Fort Worth, Panfil posted four tackles for a loss with two sacks. He also had a forced fumble, fumble recovery and pass break-up. He totaled five stops in the game.
Panfil was instrumental in the Frogs' limiting Stanford to 193 yards of offense. The Cardinal did not have a successful third-down conversion until the fourth quarter.
Panfil is tied for third nationally with his team-best seven tackles for a loss on the season. He also ranks 11th in the country with his TCU-high 3.5 sacks.
It's the second time in three weeks that a TCU defensive end has received the MWC's weekly honor. Jerry Hughes was named the MWC Defensive Player of the Week after the season-opening 26-3 win at New Mexico.