BIRMINGHAM City caretaker manager Jim Barron suffered his first defeat since taking over from Trevor Francis when Blues crashed to a 3-1 defeat at Grimsby last night.

For Grimsby the win ended a run of six straight league defeats and was built around a dominating midfield performance.

Birmingham started the game in seventh place in the First Division but it was Grimsby, the team in 18th before the game, who looked the better side.

Barron had seen his team win three and draw one since the departure of former manager Francis.

But he suffered a blow to his hopes of getting the St Andrew's job permanently with this defeat.

Barron layed the blame for defeat on his defence. He singled out left-back Martin Grainger and central defenders Darren Purse and Michael Johnson as the main culprits.

"We are normally so solid at the back and that was where we lost the game tonight," said Barron.

"There and in midfield was where they won the game. It was probably our worst defensive display for a long time."

Barron quickly turned his attention to the next game, a trip to Portsmouth.

"We've got to put this behind us, as we did the last four games without a defeat, and start thinking about the trip to Ports- mouth."

After Grimsby had scored twice in the first-half, through Michael Boulding and Phil Jevons, there was no way back for Birmingham.

Birmingham were back in the game four minutes into the second-half when Nicky Eaden's corner was headed in by Marcelo.

But any hopes the visitors had were sunk three minutes later when a clever ball behind the defence from Danny Butterfield picked out Boulding and he shot low past Nico Vaesen.