Man United manager Ralf Rangnick on Cristiano Ronaldo: Fittest player I've ever seen

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The new Manchester United manager said that he has never seen a player as fit as the one that scored two goals in the win over the Gunners.

At a news conference on Friday, the German was appointed as United's interim manager until the end of the season.

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The Portugal captain was dropped to the bench last weekend for the draw at Chelsea, and there are questions over whether he will fit into the high-pressing style of the team.

The man who was in attendance at Old United on Thursday said that he was impressed by the performance of the former Real Madrid and Juventus star and that it will be his responsibility to get the best out of him.

"You have to adapt your style or idea of football to the players you have available, not visa versa," he said.

I saw a top professional yesterday at the age of 36. I've never seen a player who is that fit at his age. He's a player who can make a difference. It's about how we can develop the whole team.

We play in the most competitive league in the world and need all the players on board. I saw yesterday that he is willing to put his input into the team. His teammates will have to do the same.

In Thursday's victory over the Gunners, the Portuguese player surpassed 800 career goals, and is United's top scorer with 12 goals so far.

The "godfather of gegenpressing", Rangnick, inspired a generation of German coaches, including the likes of Thomas Tuchel.

The 63-year-old is set to begin a two-year role in the summer after taking the reins until the end of the season.

When asked if he could continue as manager if things went well, he said he could recommend.