Marcelo Bielsa's Whites were handed an early advantage via a comical Romaine Sawyers own goal, after which Gjanni Alioski, Jack Harrison, Rodrigo and Raphinha all bagged a goal apiece.
Graham Smyth, the YEP's chief football writer, hands out the scores.
13. Pablo Hernandez
8 - Full of intent, tried to make West Brom's night worse. Demanded his team-mates kept their standards late on.
Photo by Alex Pantling/Getty Images.
14. Helder Costa
N/A - Came on late with the game dead and buried, tried his best to get involved.
Photo by Tim Keeton - Pool/Getty Images.
15. Lee Mason (referee)
8 - A quiet night. Aside from an angry Alioski had little else to deal with and got very little wrong, if anything.
Photo by Robbie Jay Barratt - AMA/Getty Images.