Despite only being in the job for a little over six weeks the pressure is already mounting on Mel and defeat to Manchester United will not help ease that at all.
Ironically, it was another under pressure boss who would heap more pressure on the Spaniard as David Moyes' side found better form at the Hawthorns.
The United manager has had problems coming at him from all angles. Just this week Nemanja Vidic, dropped today, confirmed he will play for Inter Milan next season while Robin van Persie's future was again the subject of much speculation.
However, both of those issues combined to create the opening goal at a sun-drenched Hawthorns. Van Persie lined up a free-kick on the corner of the box and Phil Jones, replacing Vidic, arrived unmarked on the penalty spot to glance it beyond a helpless Ben Foster on 34 minutes.
United had already hit the bar through Rafael and Marouane Fellaini had one cleared off the line as the visitors dominated throughout against a toothless Baggies side.
The Manchester United of old returned after the break as they ruthlessly picked off their opponents in a superb second-half display.
Wayne Rooney doubled the lead to give them breathing space with a header from Rafael's pinpoint cross just after the hour mark. The swagger was returning to Moyes' side and Rooney was the architect for the third with a deft pass for Danny Welbeck to curl the ball beyond Foster with just seven minutes to go.
The win gives United the slimmest of chances of catching the top four and they will go into next week's game with Liverpool knowing they need another win.