(Reuters) - Middlesbrough manager Aitor Karanka will forget about friendship to focus on outwitting his mentor Jose Mourinho when his team face a resurgent Manchester United at Old Trafford in the Premier League on Saturday.
Karanka was Mourinho's assistant at Real Madrid from 2010 to 2013 and credited the Portuguese with helping him take his first steps in management, but insisted that 14th-placed Middlesbrough would do all they could to disrupt United's nine-game unbeaten run.
"This is one of the fixtures I was looking forward to most. I have a lot to thank Jose Mourinho for," Karanka told a news conference on Thursday.
"It will be a special moment for me and for the team, but it is football, and three important points to play for. In those 90 minutes you can't be friends."
"I spent three amazing years with him at Madrid. It will be nice to see him. At the end of the game, we will share a glass of wine or beer or coke."
"I have to say thanks to him and to his staff so many times. I am in the Premier League because I learnt a lot with them.
Sixth-placed United, who have not lost in the league since October, are on a four-game winning run, and while Karanka has set his sights on victory, he admits it will not be easy to outwit Mourinho.
"I never go to a game aiming for a draw," he added. "We will go to Old Trafford preparing and trying to win.
"Sometimes I analyse them and I find similarities with us. But I have to do something different because he (Mourinho) knows me. I will try, but it's difficult to surprise Jose."
Reporting by Simon Jennings in Bengaluru, editing by Neil Robinson