Juan Mata feels a win over Chelsea would take on added importance for Manchester United as they continue to fight back from a difficult start to the season.
Away victories against Newcastle United and Paris Saint-Germain have boosted Ole Gunnar Solskjaer's side as they look to put the 6-1 home humbling against Tottenham behind them.
United host Frank Lampard's team on Saturday and are looking to win three consecutive top-flight meetings against Chelsea for the first time since September 1965 under Matt Busby.
The Blues are winless in their last seven Premier League outings at Old Trafford, but Mata is aware of the threat posed by his former club, particularly after adding Timo Werner, Kai Havertz, Ben Chilwell, Hakim Ziyech and Thiago Silva in a busy transfer window.
"Of course we are aware of their dangers, as we know they have signed many very good and important players," Mata told the Pitch to Post podcast.
"Attacking-wise, defending-wise they have got a great squad. So we know what they are capable of and we need to be ready for that.
"But also we need to think we are playing at home and if we play our football hopefully we'll have chances and create scoring opportunities to get the three points.
"And of course, they're a big rival for us because they're challenging for what we're challenging. A victory against them will be important, although we know it's difficult."
Mata also praised his old team-mate Lampard, adding: "You could feel from the first day that I arrived to Chelsea's dressing room that he was a very intelligent man.
"He knew a lot about football and he understood the game really well as a player. You could imagine that he would be a very good manager, like he's showing now."
Only once in their league history – in 1930 – have United lost each of their opening three home league games, but Mata is more confident after wins in the top flight and on the continent.
"It was exactly what we needed after the defeat at home," he said about the Newcastle and PSG triumphs.
"You want the next game to come quickly but unfortunately there was the international break, so we prepared really well, we trained hard over that week and then we got two very good performances.
"So we're very happy with the week – but we want to keep this momentum going."