Gus Poyet was unhappy with his side's "comic" defending as they lost 6-1 to Liverpool in the FA Cup fifth round.
Three own goals on the day at Anfield saw the Seagulls exit the competition in embarrassing style.
"It's difficult to analyse, because I think it was always a matter of holding them and making sure we didn't concede any silly goals," Poyet told ESPN
"For long periods in the first half, I think we were in the game. But the second goal changed it.
"If we had gone to half-time at 1-1, the message from the opposition changing room would have been very different, but then in the second half three or four of the goals were comic."
The Uruguayan also claimed that the result has proved that his team are not ready for the Premier League.
"People think we are ready for the Premiership, but we are not," he added. "If you want to one day get to the Premiership as a team or as a player you need to learn.
"The quality, the strength, the power the players have got is amazing. This is a top-six team, but I don't think anyone likes to go to places in the top six and finish the game 6-1."
Brighton will now look to dust themselves down before their Championship encounter at Hull City on Wednesday.
