Leading 1-0 for practically the entire match, de Gea allowed a weak goal by Clint Dempsey in extra time that resulted in a draw for the Red Devils.
According to ESPN's Miguel Delaney, Man U is shopping the 22-year-old Spaniard, but it's reported a move won't take place until the summer.
Granted, it was one large mistake that has some questioning de Gea's play, but his guarding of crosses has come into question lately.
In his piece, Delaney draws comparisons to the mistake of another big-name goalkeeper:
The mood and response following his latest mistake is said to be akin to when Tim Howard spilled a shot against Porto in the 2003-04 Champions League last 16, allowing Costinha to score the late goal that put United out of the competition.
While some Red Devils fans may be upset to see de Gea sold, he hasn't exactly lived up to his £18.5 million deal, as Delaney notes.
Delaney also suggests that there's reason to believe the goalie is still trying to adjust to life in England, which could be affecting his game.
With the offense Manchester United boasts, it can afford to sell de Gea and put that cash to better uses.
The talents of Robin Van Persie, Wayne Rooney and Javier Hernandez should leave little doubt in Red Devils fans' minds about the state of the club with a possible departure of de Gea.
With the de Gea experiment not going as planned, the Red Devils could look toward Victor Valdes, though ESPN reports there hasn't been any contact with the Barcelona keeper.
With his performance waning, it sounds like de Gea's days with the Red Devils are coming to a close.
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