Huddersfield Town have beaten Birmingham 4-1 in extra-time to book a fifth-round FA Cup clash with Manchester United.

The Terriers went behind when their Championship opponents struck through Che Adams.

Fortunately for David Wagner's side, City defender Marc Roberts diverted the ball into his own to tie things up.

Steve Mounie, Town's record signing, proved his worth in when he nodded home a Scott Malone cross four minutes into extra-time.

Goals from Rajiv van La Parra and Tom Ince cemented the victory for Huddersfield.