Manchester United midfielder Nemanja Matic says his success at former club Chelsea demonstrates that he has nothing to prove in Sunday's Premier League clash between the two sides.
Matic joined champions Chelsea in 2014 under former manager Jose Mourinho and helped them win two league titles and a League Cup in three seasons.
The Serbian was reunited with Mourinho at United in July and has been instrumental in the Manchester club's strong start this season as they sit second in the league standings and top of their Champions League group.
"I feel when I played there, I showed them my quality. We won the title twice and also two cups, so I don't have to prove to them anything. I just have to prove something to my new club," Matic is quoted as saying by The Guardian.
The 29-year-old said he was not concerned about his reception at Stamford Bridge but is wary of losing to the champions as it would give rivals the opportunity to insert themselves into the title race.
"We know we must respect them," Matic added. "They are a good team, they're champions and it's going to be a hard game for us, but we also have our own qualities.
"The Premier League is difficult... You lose two games and the other teams are there, so it's important not to lose points, of course, but there's a long way to go."
Former Chelsea playmaker Juan Mata was part of the United team that lost 4-0 to Antonio Conte's side last season but the Spaniard believes the side's focus is fully on the coming fixture.
"There's not revenge on my mind. (They are) totally different games, what happened last season, happened last season and now we have to think in the present," Mata said.
"It's always a difficult game playing Chelsea away but we will try our best.
"There is a lot of pressure around the game but obviously we will try to play our best football and come back to Manchester with three points."
United trail leaders Manchester City by five points and last beat fourth-placed Chelsea in an away league game in 2012.