Ragnar Sigurdsson said Iceland didn't feel under any pressure against England in their 2-1 Euro 2016 round of 16 victory in Nice.
Sigurdsson equalised for Iceland moments after England had taken an early lead through a Wayne Rooney penalty.
And the 30-year-old Krasnodar defender played an important part of keeping England at bay as they searched for an equaliser.
He said: "It went well. We didn't feel that they created any chances. We were just heading away long balls. I wasn't stressed in the second half."
Meanwhile, Lars Lagerback, Iceland's joint coach, added that he wasn't surprised by their victory.
The former Sweden manager who is now unbeaten against England in seven games said: "It's no surprise. You can always win. Football is about teamwork.
"When Jamie Vardy came on he had the pace but we kept it under control.
"This is without a doubt the biggest result in Icelandic football history. We've shocked the world."
Lagerback paid respect to Roy Hodgson, a man he has known for 40 years and learned a lot from.
Following the England manager's resignation, Lagerback said: "Of course it is a great victory but the coach role, as you all know, is not the easiest.
"Part of why I am sitting here now is thanks to Bob Houghton and Roy Hodgson when they came to Sweden, so I would like to express my big respect for them because I learned a lot from them.
They changed the training methods and the coaching education in the long run in Sweden and I was really, really benefiting from that.
"Among the big, big joy of course with the fans, the players and everything, big respect to a really, really good coach also."
Lagerback, who plans to retire after Euro 2016, also backed his players to find more success in their club careers.
"We're really doing well defensively -- everyone is well organised, doing their jobs and reading the game," he said.
"The attacking part was also really good. Football is about winning and scoring as many goals as you can. This team has really shown what it can do.
"The result can influence their football lives because some of the players deserve contracts at higher levels than they are now."
Iceland's other joint coach Heimir Hallgrimsson believes the side are capable of achieving similar results in the future.
He said: "I was more relaxed than during the game against Austria. If someone had told me a few years ago that we would reach the last eight I have to say I would not believe it.
"No obstacle is too big for these guys now."