Everton manager Ronald Koeman was left dumbstruck by his players' sloppy attitude as they threw away the lead to lose 2-1 to Leicester City in the FA Cup third round.

The Toffees dominated the opening hour at Goodison Park and finally went ahead in the 63rd minute through Romelu Lukaku, only for two goals inside three minutes from Ahmed Musa to turn the tie on its head and dump Everton out.

Koeman rounded on his squad's "sloppy attitude" after handing Claudio Ranieri's side just their second away win of the season in all competitions.

Very disappointing, because I think we did well," Koeman told the club's official website.

"We dominated the game, we scored the 1-0. It's always difficult against Leicester because they were very defensive.

"It's unbelievable how we lost the control after 1-0.

"[We had] a sloppy attitude, [we were] not good [at] what we did before - good pressing on the ball, good defensive organisation, and we were punished by two goals.

"The team played well, but you need to continue with the same attitude.

"I don't understand why we dropped back, because they don't create that space [otherwise].