The defending champions are currently seven points behind fourth-placed Liverpool after a surprise 2-1 loss to Stoke City at the Britannia Stadium on Saturday.
Without a shadow of a doubt. The squad is definitely capable [of it]
But Fletcher, who returned to the first-team in December following a prolonged spell on the sidelines with ulcerative colitis, backed the Red Devils to secure Champions League football next season.
Asked if United could finish in top four, Fletcher told Sky Sports News: “Without a shadow of a doubt. The squad is definitely capable [of it].
“We have to go on a run now, there’s no doubt about that. Let’s finish the season strongly and get in the Champions League, and let’s carry that through to next season.”
Fletcher called on his United team-mates to showcase the club’s trademark character following a staggering eighth loss of the season at Stoke.
“It’s all about character now, there’s no doubt about it,” Fletcher added.
“The team has been written off and everyone has had so much to say about the situation.
“Now it’s time for the players to step up and prove people wrong and finish the season strongly.
“That’s the goal.”
He added: “I’ve been here personally. You can come from it. You need belief and luck but the biggest thing is to dig down deep inside yourself.
“I know this team is capable and I see how much they’re hurting and I’m sure we’ll come through it and be a success.”
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