In their final Premier League 2 fixture of the season, Wolves conceded the opening goal just before half-time, followed by four further goals in the second-half.
Sellars believes that there was nothing between the two teams in the opening 45 minutes, but felt the goal just before the break changed the game.
“I thought we started quite brightly,” said Sellars.
“We got into some good situations but we didn’t really make enough of it.
“First-half was pretty tight and I thought we gave as much as they did.
“Conceding just before half-time was obviously disappointing, a disappointing goal.
“I think the goal just killed the confidence of the lads.
“The second-half performance, we just caved in really.
“What I didn’t enjoy was that I didn’t really feel they did anything about it, too many of them collapsed under the pressure.
“Fair credit to Brighton, I thought they were excellent."
Despite finishing the campaign with a defeat, Sellars believes the season overall has been positive, and also outlined his aims for next term.
“To finish on that obviously leaves a bit of a sour taste, in terms of the performance and the score.
“But overall, it’s been positive.
“Morgan’s (Gibbs-White) progression, Bright (Enobakhare), Connor (Ronan) going out on loan, Sylvain (Deslandes), Oscar (Buur Rasmussen) has come in and had an effect on the first team, and Donovan Wilson scoring at Southampton.
“We’ve had some positives but we need to work hard over the summer.
“We’re going into the Premier League so if we’re going to get players into the first team, then we can’t just be living off your Morgan’s and your Bright’s, we need to be producing more.
“As an Under 23 team, we need to recruit some better players to put the players here under pressure and give us a chance to compete.”
