Chelsea manager, Enzo Maresca, has bemoaned the lack of VAR in the early stages of the FA Cup.
Kaoru Mitoma appeared to have handled the ball before lifting the ball over Robert Sanchez, for what proved to be the winner in the fourth round tie on Saturday night.
Georgino Rutter had cancelled out the Blues’ early lead, which they got through Bart Verbruggen’s own goal.
Mitoma’s goal was allowed to stand, a day after Harry Maguire’s controversial winner for Manchester United against Leicester City.
Maresca told BBC Sport: “We controlled much better the first half. The second half the only shots they had we conceded a goal from.
“I think the handball [before Brighton’s second goal] is quite clear. In the last two or three days there were many different moments in different games. Without VAR it’s complicated.
“We tried to come here and make our game. We had a few chances at 2-1. Now we can focus on the Premier League and Conference League.
“We always try to win the games. But in the same way you have to take the consequece of the result.”