The Red Devils have struggled to cope with the summer departures of experienced trio Patrice Evra, Rio Ferdinand and Nemanja Vidic.
They have the players there to get to the top four, without a doubt, so once they get their defence sorted I sure they’ll be fine
Louis van Gaal’s side have already conceded 10 goals in seven Premier League games, including five at King Power Stadium in September.
And Sunderland defender O’Shea, who won five Premier League titles during his United career, backed his former side to find some consistency.
O’Shea told talkSPORT: “No I don’t think so.
“I think they’ve just been very unfortunate with injures, and consistency for a back-four is very important.
“If Jonny Evans stays fit he’ll be crucial for them, he’s a very good player, he talks and organises the defence.
“If they’re chopping and changing, with Phil Jones, Chris Smalling and the new signings as well, they can’t get a run of games together, and consistency is the key for any team aiming for the top-four.
“A lot of people have been talking about the team’s experience as well, and with losing Rio [Ferdinand], Vida [Nemanja Vidic] and Patrice [Evra] it was always going to be tough for them this season.
“But it isn’t a question of personnel, I think they have the players there to get to the top four, without a doubt, so once they get their defence sorted I sure they’ll be fine.”
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