Mark Hughes slated his players for lacking professionalism after billionaire club Manchester City were humiliated by hard-up Brighton in the Carling Cup.
City were sent home with their tails between their legs after the League One side came through 5-3 on penalties after a dramatic 2-2 draw last night.
Brighton's Dutch keeper Michel Kuipers saved Michael Ball's penalty in the shoot-out allowing Matt Richards to coolly convert his spot-kick and spark an old-fashioned pitch invasion at the Withdean Stadium.
The drama came just two days after confirmation of City's £200million takeover by the Abu Dhabi United Group.
Hughes insisted he had no regrets about resting £32.4million Brazil star Robinho and £9million winger Shaun Wright-Phillips after Brighton bounced back from a Gelson Fernandes strike just after the hour.
Glenn Murray dramatically equalised in the 89th minute and on-loan substitute Joe Anyinsah fired Brighton in front in extra time.
Stephen Ireland levelled matters again but the shoot-out deservedly went the Seagulls' way.
Hughes said: "We are disappointed because we had a strong enough team out there to have won this game and I thought we looked very comfortable in the second half.
"But we missed chances when we should have been professional enough to have seen it through to the end after taking the lead.
"Once it goes to penalties it can go either away so we mustn't dwell on this result but you never want to go out of any competition.
"There is obviously a lot of focus on us at the moment but I don't know if I'm more embarrassed than angry about going out.
"At least we were able to give game-time to some players who needed it - and to be honest the need was pretty evident at times."
Hughes refused to blame the antiquated conditions at Withdean Stadium, a makeshift facility with temporary stands which Brighton rent for their home games in the long wait for a new stadium to be built at nearby Falmer.
Hughes said: "It's similar to several places I've been in Europe and the players should be able to cope with it."
Brighton boss Micky Adams said it was the criticism his team took for losing 1-0 at home to nine-man Walsall last Saturday that fired them up for the shock win which earns a third-round clash at home to Derby.
He said: "The boys were well up for it and needed to do something big after the reception they got after Walsall.
"I'm not going to crow about beating the so-called richest team in the world because as a player and a manager I've been on the wrong end of these type of results.
"All I can say is that my boys were spot on for their endeavour and their pride and they deserve all the plaudits for a fantastic response."