Two defensive lapses cost Fulham dear as they were beaten 2-0 by Middlesbrough on Saturday.
Goals from Adam Reach and former Chiswick park player Albert Adomah condemned Kit Symons' side to defeat at the Riverside.
And the caretaker boss admitted that sloppy defending had been the reason his team had lost.
“If you are outplayed and the other team deserve to win, I've got no problem with that, but I honestly thought we should have got something out of it," said Symons.
“We conceded a very, very sloppy goal right at the start of the second half, which gives you a bit of a mountain to climb."