Was he mostly gash though Lou?
The entire team were gash from September to November.
Sigurdsson is as liable as any of them, yes, but he came into a squad where the manager had no idea how to use him or what system to play.
He was chucked in without having a pre-season (and yet there's still people saying he should just be able to slot right in because if you cost £45m then match fitness just isn't an issue!), and into four different roles (RM, AM, LM, CF).
His performances started to pick up as his sharpness came back.
That game against Southampton he was the only player to play anywhere near their level.
And by the time Sam came in he'd started to actually play well. He was linking up great with Rooney - despite Sam's comments (against several facts) that him and Rooney couldn't play together.
He continued to play well from that point until he got injured. Whether playing from the left - where he had no support from Martina so had to try and do it all by himself, and then had to track back and help Martina out - or centrally.
He's had a 6/10 season. But in terms of players who have something to prove, I'd say while he certainly does need to improve, he's far down on the list of players who actually need to step it up and prove their worth keeping.