The Red Devils are in fifth place and knocking on the door of the top four.
And Lampard acknowledged his rivals, who they will also meet in the FA Cup semi final.
Lampard told reporters: “They’re closest, they’re a very strong team, they’re in great form for a long period of time.
“They have got really good individual players. You have seen the momentum they have gained across their front three, all scoring, lots of goals.
“They’re the biggest threat from behind, but this is the Premier League. It looks that way today, but it’s how each team finishes the season.”