Fulham boss Slaviša Jokanović was left ruing a moment of defensive madness as Derby stole a point in a 1-1 draw at the Cottage.
Oliver Norwood put the Whites ahead on the half-hour mark with a powerful free-kick from 25 yards out, but Matej Vydra snuck behind the Fulham defence five minutes after the interval to pull the Rams level.
Jokanović said: “We made one mistake and paid a very expensive price. They scored the goal without making any dangerous situations in our box before or after.
“We are also not clinical enough in the box but this is not news to us.
"We are frustrated because we didn’t finish a good performance. We didn’t win tonight but with this confidence we can win on Wednesday night."
Fulham arguably should have had two second-half penalties after Ryan Sessegnon was tripped inside the box and Tom Cairney’s shot appeared to strike the defender’s arm.
Jokanović said: “The referee didn’t spot two penalties. He didn’t show enough personality to point to the spot.”
Cairney was on full-form following a long lay-off from a knee injury.
Jokanović said: “Tom Cairney can make people play better with him – all the team play at the highest level around him.”
“We also played an eighteen year old (Edun) and he played very well for one hour and also we played Luca De La Torre and they have both shown they can play at this level. They didn’t seem scared to play against one of the most experienced teams in the Championship.”