McDermott was so keen to sign the 25-year-old from Newcastle United that he visited him in Dubai in an attempt to convince Guthrie that Reading was the club for him.
Guthrie revealed that he was impressed by McDermott's determination to clinch his signature and had agreed to join the Royals by the time he was back in England.
"I was in the last year of my contract and there were numerous meetings between my agent and Newcastle. We couldn't agree on anything and I was talking to a number of clubs," said Guthrie.
"The manager came to see me while I was on honeymoon in Dubai and when I came back I'd signed. I was fine with him coming during my honeymoon. It was surprising and a nice gesture. It showed intent.
"I mentioned it to my wife Rebecca and she was glad to get rid of me because we were coming to the end of the holiday. It went down well. Once I met him and listened to what he wanted to do, it was just a case of me getting home and signing the papers."
Guthrie has made five appearances for Reading since joining, scoring one goal.