Former Manchester United defender Wes Brown has claimed that Jose Mourinho's side can still secure a Premier League top-four finish, but they "need to be beating the big boys".
The Red Devils are currently fifth in the table, four points behind fourth-placed Manchester City, but Jose Mourinho's side have a game in hand.
However, United's eight remaining games include a home game with Chelsea on Sunday, plus trips to Man City, Arsenal and Tottenham.
Brown, who played for United between 1996 and 2011, told Sky Sports News: "They need to win [the Chelsea game]. It is getting to that stage in the season now where they need to be beating the big boys.
"Chelsea have been brilliant all season and. if [United] can get past that hurdle, then the remaining games become very important.
"Fourth is still on. It is difficult, with the teams above, but hopefully they have still got a chance - and in the Cup (Europa League) as well."
Brown has made a total of 232 appearances for Man United and won 14 trophies with the club, including five Premier League titles and two Champions League cups.