I actually don't see that happening.
He's not putting up great numbers or statistics, has lost a spark about him; pace, agility. Is no longer a young player and should be finding his stride - 22 in the modern day is when you're expected to bed yourself into a team, if you're a genuine top talent.
I imagine Getafe will be his level. In Spain, Italy or Germany, a mid-table team will be where he's suited.
Why would Getafe be his level when he previously excelled at Manchester United (as a teenager no less) ? Therefore if not United, it would seem that another big club of comparable stature would be his level - Madrid, Barca, Athletico, Juve, Bayern, PSG would be among the suitors. If there is a perception that bigger clubs aren't after him in the present, its more so due to the fan protest risk they would want to avoid taking on, not his capability as a footballer.