Disappointed Middlesbrough boss Gareth Southgate admitted his side had been poor in the 3-0 defeat at Fulham.
However, Southgate could not understand the referee's decision to award the Cottagers a penalty when Tony McMahon was adjudged to have handled the ball.
He said: "It's been a long and miserable afternoon for us. We weren't good enough. We didn't pose enough of a threat and, in the final third, we weren't up to standard.
"We've been indisciplined in the way we've defended as a team.
"We knew, coming here, Fulham don't give anything away. The first goal was always going to be crucial and we conceded a poor one.
"But what I think is a pretty unbelievable penalty decision has a big bearing on the rest of the game.
"That's three weeks on the spin decisions have gone against us. The pictures are there for everyone to see. How Tony McMahon was to get out of the way of it, I have no idea.
"They're costly decisions, but we have to have a look at ourselves first and ask have we done enough to get back into it and have we defended well enough as a team?
"We find out a lot more about ourselves on afternoons like this than, say, last weekend."