Not in a long time have Manchester United been so desperate for a win.Four games without victory finds Jose Mourinho and the players under huge pressure to turn their season around before it becomes critical.The Red Devils have also gone four home games without winning, so Saturday's clash with Newcastle United is hugely important.Win and the pressure will be alleviated; lose and there's a good chance Mourinho will be sacked.Mourinho is all too aware of the potential consequences of defeat and speaking ahead of the game he said three points is far from guaranteed, despite Newcastle languishing in 18th."We can win against Newcastle but it is a tough match," the Portuguese said on Friday. "We can win, we want to win."We have [the chance] to win the match but I refuse to say we have three points in the pocket. I have to respect the opponent."I have to respect the manager (Rafa Benitez) with a history of trophies and a history of knowhow. That is the way I was brought into life and football: to respect."How Mourinho will line up his side against Newcastle is anyone's guess considering all the changes he's made recently.In last weekend's defeat to West Ham the 55-year-old dropped Antonio Valencia, Alexis Sanchez and Jesse Lingard and opted for a back five.Man Utd to beat Newcastle 3-1 (13/1)*And then against Valencia in midweek he restored Valencia and Sanchez to the starting XI and reverted to a standard 4-3-3 formation.So what's his plan for Newcastle? Well, it would appear Valencia is out of the game one way or another after he liked an Instagram post saying "Mourinho Out" earlier this week.The 33-year-old right-back has just tweeted wishing his teammates the best for the Newcastle game. No injuries have been reported.

"Good luck to all my team. Glory Manchester United!" he wrote.

Strange. Valencia's tweet has drawn a big reaction from United fans, who are hoping the Ecuadorian has indeed been dropped - hopefully for Diogo Dalot.

Dalot, 19, is an exciting young talent and United supporters are keen to see him play more often after he was named on the 40-man shortlist for Golden Boy.

*Odds subject to change