"We outplayed them and outbattled them, created four major chances and they did nothing. We had 13 shots, they had one and our keeper hardly touched the ball.

"I hate losing home games but for me that was one of the best first-half performances in a long time."

However, he was also critical of his side's lack of tempo and willingness to get behind the deep-lying Birmingham defence after the interval.

He said: "The second half was the disappointing part. We needed to play much quicker, get forward and behind them and we just didn't do that.

"It's difficult when you're playing against a 5-4-1 formation but I expect more energy and pace instead of just having a few five-minute spells where we looked lively."

Frank refused to be drawn on the fate of striker Neal Maupay, who sat out the game amid growing Premier League interest ahead of a proposed £20million move.

He also refused to comment on speculation that the Bees are lining up at least three new signings ahead of deadline day.

"I'm delighted with the four new players we had out there today and they will only get better as they understand the way we want to play," he said.

Birmingham coach Pep Clotet admitted his side rode their luck in a one-sided first half but hailed their effort and determination to close the game down after the break.

"It was a very well organised performance but we wanted a better display than the one we had, but I don't take away from the effort of the players," he said.

"We didn't manage to challenge Brentford for possession and from the first minute we found it difficult to close a few gaps they were creating. They had great chances but unfortunately for them and fortunately for us they didn't go in."

He added: "In the first half they deserved more and we deserved less but when we scored we got more confidence and grew more comfortable.

"As the game advanced, we closed those gaps they were using in the first part of the game and we felt our defence was more comfortable.

"Unfortunately, we couldn't turn the balls in to counter-attacks but for us at the end of the day I have mixed feelings – we could have done better in aspects of the game, but when it comes to attitude and effort of the team I can't fault them."

Clotet also paid tribute to the Blues fans for sticking with the side after a nervy first half: "When Brentford hit the bar three times it was tough and we had to reorganise, but the fans were always on the side of the team.

"It's a good start but I'm not 100 per cent happy because there were definitely aspects of our play that we need to get better at."