The Dane was handed a full 90 by manager Jose Mourinho.
"It was nice to get some minutes," he told Chelsea TV. "I knew I'd be playing after the Man United game so I had some time to prepare myself which was good.
"I've played at right-back before but it's been quite a while since I did that so I was just trying to see my clips from before, see what I did and try and do it again.
"The manager told me to be myself, play how I normally do and I would be fine. JT, Gary Cahill and some of the other older players told me to not rush it, play it as simple as long as I could then when I felt a bit more comfortable risk it a bit more.
"I got cramp with 10 minutes left and I had to fight through it but I did which was good."
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