Roberto Martinez cited Everton's mental strength as the key to their superb 3-0 win over Manchester United at Goodison Park.
Martinez's players executed his game-plan of sitting deep and hitting United on the break to perfection on Sunday, and were rewarded with goals from James McCarthy, John Stones and Kevin Mirallas.
"[The players deserve] Huge credit because we were facing a very good side," Martinez told Sky Sports.
"We had to be at our best and truly I felt that, as a team, we were at a fantastic level. In every department we were very, very good."
Speaking about his ploy of looking to hurt United on the counter, Martinez added: "You know Manchester United are a very good side with the way they keep the ball.
"We were quite happy to allow them to have it in certain areas but we showed an incredible intensity [to win it back] and that's how McCarthy's goal came.
"From then on, we were always a threat. Obviously Manchester United had to rush things a bit more which played into our hands.
"To keep our concentration for 90 minutes and keep a clean sheet - I thought it was magnificent and showed an incredible mentality."
