Jose Mourinho has claimed he knows the names of the Middlesbrough players who were responsible for the sacking of Aitor Karanka, ahead of Manchester United’s trip to the Riverside on Sunday.

Karanka was dismissed from Boro this week after seeing his side drop to 19th in the table, three points from safety, and get knocked out of the FA Cup to Manchester City.

Mourinho and Karanka are close friends from when the latter was the Manchester United boss’ assistant at Real Madrid before the Spaniard joined Boro four years ago and got them promoted to the Premier League.

And the Portuguese said he was one of the first people to call Karanka after hearing about his sacking on Thursday and insisted he knew who in the Boro dressing room is to blame.

“I think he deserved to be sacked,” Mourinho said, sarcastically.

“In this case, I know the names.

“In the first year he arrived, the team was going into League One and he saved the team.

“In the second year, he took the team to Wembley, to play the play-off final. In the third year he had direct promotion. So I think in the fourth year, he deserved to be sacked.”

Mourinho has always been a staunch supporter of Kananka and his dismissal will give the former Chelsea boss all the more motivation to take the three points at the Riverside at midday on Sunday.

United remain in sixth place in the Premier League, six points behind fourth-placed Liverpool but with two games in hand.

Winning both of those would put them right back in the race for a Champions League place but Mourinho knows it will be extra tough for his side given that they are the only top four-chasing side who is still involved in European competition.

“It's more difficult, obviously it is more difficult,” he said. “We played 11 matches in the last six weeks.

Karanka was Mourinho's number two at Real Madrid (Getty)

“It's going to get worse for us and it's going to get easier for the other five teams. Before it was only Chelsea and Liverpool who were not in Europe. Now also Arsenal, Tottenham and Manchester City are also out. So obviously it is very difficult for us.

“What do you want me to do? Do you want me to go to Middlesbrough and play with Nicky Butt's boys?

"Then what would say Hull City and Sunderland and the teams that are playing against Middlesbrough for the relegation battle?