Arsene Wenger congratulated Birmingham on their Carling Cup triumph but admitted it was frustrating not to end Arsenal's trophy drought after the defeat at Wembley on Sunday.
The Gunners went into the tie as firm favourites to end a much-publicised wait for silverware that stretches back to the 2005 FA Cup, but Alex McLeish's Blues emerged as deserved 2-1 winners.
The winning goal came in the 89th minute when Obafemi Martins prodded the ball home following a mix-up between Wojciech Szczesny and Laurent Koscielny, which again highlighted Arsenal's defensive shortcomings.
Wenger is refusing to blame Szczesny but concedes his team 'have regrets' over the way they lost.
"I wanted to end our wait for a trophy today," he told Sky Sports.
"The only thing you can guarantee is the quality of the performance and the attitude. That is of course very important for us.
"We will have to wait a little bit longer."
Wenger added: "We got what we expected from Birmingham - they are a team who fight very hard and cause a lot of problems from long balls.
"Both teams gave everything. Congratulations to them - they got the trophy - but we have regrets with the way we conceded the (Martins) goal.
"What can you say? You have to be positive because he (Szczesny) is a young boy. He has to pick himself up from that goal and hopefully he can do that."
Van Persie scare
An injury to Robin van Persie could also add to Arsenal's woes, with the Dutch striker taken off as a precautionary measure midway through the second half.
"We are in good positions everywhere but we play so many games and we can't go on losing players," he said.
"We lost Cesc Fabregas in the week and now Robin van Persie is not in good shape after this game.
"It's a knee problem - we will have to assess it tomorrow."
Who was Birmingham's man of the match in the Carling Cup final?