Championship league leaders West Brom cruised past Peterborough to secure their place in the FA Cup fifth round.
Roman Bednar celebrates scoring the first goal with Filipe Teixeira
Roman Bednar slammed in the opener from inside the six-yard box after Craig Beattie's shot across goal.
Joe Lewis tipped James Morrison's shot on to the post but after Beattie had fluffed his attempt from the rebound Robert Koren swept home from 12 yards.
Kevin Phillips' spot kick sealed it after Craig Morgan tripped Jonathan Greening and was subsequently sent off.
The League Two high-fliers showed plenty of promise and were twice denied by goal-line clearances, but the quality in possession of Albion proved decisive as they ruthlessly punished some slack defending.
Bednar's strike, which crashed into the top corner, dampened the atmosphere inside a packed London Road and Tony Mowbray's side further extinguished any hopes of an upset with a second in the 14th minute when Morrison drove home.
And the tie was put beyond Posh's reach on 58 minutes after a Morgan's trip.
A slack header by Kieran Charnock was turned back towards goal by Morrison and Beattie cleverly flicked the ball on to release captain Greening into the area.
Greening took a touch but was denied a shooting opportunity as Morgan tripped him and referee Jonathan Moss had no hesitation in awarding the penalty and sending the Wales international off.
Phillips hammered the ball low into the bottom left corner to reserve Albion's spot in the fifth-round draw.
Peterborough: Lewis, Newton, Morgan, Charnock, Day, Whelpdale, Keates (Mitchell 76), Lee, Boyd, Mackail-Smith, Mclean.
Subs Not Used: McKeown, Crow, Gnakpa, Blanchett.
Sent Off: Morgan (57).
West Brom: Kiely, Hoefkens, Albrechtsen, Cesar, Robinson, Morrison, Koren, Greening (Brunt 64), Filipe Teixeira, Bednar (Phillips 46), Beattie (MacDonald 78).
Subs Not Used: Steele, Barnett.
Booked: Hoefkens, Beattie.
Goals: Bednar 7, Koren 15, Phillips 58 pen.
Ref: Jon Moss (W Yorkshire).
BBC Sport Player Rater man of the match: West Brom's Robert Koren 7.83 (on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.