If United sign Leighton Baines will they sell Patrice Evra in January?
An obvious dilemma would therefore be created regarding current first choice, Patrice Evra, and what would become of him?
Evra may have known his number at United was up in the summer when Moyes first attempted to sign Baines, but has continued to hold down a first team spot at the Red Devils, recently setting up a winning goal for Javier Hernandez in a 3-2 win against Stoke.
Evra you would imagine would not give up his first team spot without a fight, nor is he the sort of character to shy away from competition.
That should certainly worry Leighton Baines ahead of a January transfer, because of his own World Cup ambitions - aiming to secure a starting spot ahead of Ashley Cole, he would not want to risk spending time on the substitute's bench, unable to force his way into the United team.
Such is Evra's character, it would be quite easy to see him stepping up his game upon Baines' arrival, making life difficult for Moyes and the new addition.
This is why it is easy to see Moyes cashing in on the left-back in January if Baines is brought in, simply to make his own life easier and perhaps even as a condition of persuading the Everton defender to join.
Evra will not be short of suitors in France where he has a high profile, still the first choice left-back for his country, and his former club AS Monaco are already rumoured to be keen.
Just like he signed midway through the season in 2007, leaving midway through 2013/14 could be how David Moyes sees Evra's United adventure ending.
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