If his attitude and form don't improve dramatically before Christmas, some hard decisions will have to be made. Van Gaal has a history of not respecting reputations, and he may well go back on his promise to play Rooney if he deems it necessary.
When Burnley first entered the Premier League back in 2009 they may have been relegated finishing 18th, but at least Turf Moor became somewhat intimidating as they won their first four fixtures at home. So far two draws and a defeat hasn't set them up anywhere near as well as for that season, and they went back down then!
Losing your best player will always have an adverse effect on a team. Liverpool have struggled this season following the sale of Luis Suarez to Barcelona, while Tottenham failed to sufficiently replace Gareth Bale after his record breaking move to Real Madrid. Athletic Club are following suit having floundered through the first 6 weeks of the campaign on the back of Ander Herrera's big money move to Manchester United.
After being linked with a move to Napoli in January, followed by a potential return to France over the summer, Capoue is establishing himself as a first team regular at White Hart Lane this term. Pochettino has placed a lot of faith in the midfielder and now fans are seeing the best of the 26-year-old as he shines in front of the back four and if Spurs are to enjoy some long-awaited success this season; Capoue may play a crucial role in this dream becoming reality.
There has been plenty of class from the 35 sides who didn't go down straight away. Some even surprised everyone and punched well above their weight when back (or debuting) in the big time. Here are five of the best.
Major squad overhauls usually have an adverse effect on the team - take Spurs' season in the wake of Bale's multi-million pound move to Real Madrid - but Koeman has taken everything in his stride and built a side capable of matching Pochettino's from last season.
Ulloa's aerial ability means he has developed a statistically calculated strength of 'headed attempts', and with Riyad Mahrez and Jeffrey Schlupp breaking down either flank, the aim is to put the ball into the danger zone where the striker can maximise this facet of this game.
Big Sam has done exactly what has been asked of him and fans can now look forward to every game, something that has not been true for a long time. So after all of this, has he done enough to win over even his biggest critics, or is it still too early to tell?
The way Liverpool are headed at the moment, it's entirely possible that they'll be left to scrap it out with Manchester United for the last place in the top six, which would be a rather painful comedown after their title challenge last season.
At the same stage in his career, Leon Jeanne was a highly hyped, pacey, skillful midfielder with the world at his feet. He had a few off-field issues, but City took a chance on him. Now he plays for Weston-Super-Mare. Nothing against Weston-Super-Mare. It's a nice place. I visited once. But let's hope Morrison doesn't go the same way.
Chelsea look ominous, Liverpool and Man Utd look unlikely to compete at the top due to complete defensive inadequacy, while the North London teams look set for another groundhog season of raised then dashed hopes - though hope then dejection has pretty much already taken place at Spurs.
Aston Villa's fortunes appear to be changing this season. Ten points from four games represents a remarkable start for any team in the Premier League and Paul Lambert's side currently occupy a lofty second place in the table.
To bring out the best in a player of Özil's quality, a manager must build a team around him. Wenger strived to do this last season with 24 of his 25 league starts coming in the number 10 role. It's understandable why the Frenchman would do this, with the attacker widely regarded as one of the most creative players in world football.
While transfer negotiations were sill going on, the team were struggling on the pitch. But now that the window has closed and the squad is complete, United look an altogether different beast.
Many would argue that a stroke of luck in the transfer market which led to the Tyneside club signing the likes of Yohan Cabaye, Hatem Ben Arfa and Cheick Tiote on the cheap, made Pardew look better than he is and have helped in prolonging his stay. Now that the dust has settled, his tactical and man-management deficiencies seem to be showing him up for what he really is.
For all the talk of Ozil needing pace to be able to make the most of his creative abilities, given his current form and inability to do the small things properly, the return of Walcott could - perhaps should - see Ozil lose his starting place.