Downing own goal starts the slide as Birmingham leapfrog Boro

But Middlesbrough abrogated their responsibilities 24 hours later to hand the Scot his first triumph at St Andrew's.

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Birmingham's new manager was rewarded for his generosity of spirit with the club's biggest victory since their return to the top flight as the Teesside club caved in at crucial times.

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McLeish had shunned traditional Christmas Day training, telling his squad to put their feet up. It was to prove a wise call as three deadball situations proved decisive.

Stewart Downing sliced a Gary McSheffrey free-kick into his own net to set Birmingham on their way. Mikael Forssell made it two by stabbing home a corner on the stroke of halftime and a penalty in the dying moments wrapped up a tidy afternoon's work for the hosts.

The scoreline was harsh on the visitors, who will undoubtedly enjoy more fortuitous 90 minutes in the Barclays Premier League this season. But this triumph lifted Birmingham four points clear of the relegation zone after they had been sucked perilously close to trouble after two wins since mid-September.

A similar victory over Fulham on Saturday will give McLeish breathing space as his team face three of the top four in January.

It wasn't pretty — it rarely has been at St Andrew's — but this set of players do have guts.

McLeish said: 'Having given them the day off with their families, we got payback from the players. Their professionalism has been of a high standard.

'They had worked hard on Christmas Eve. There were some great individual performances out there. We cut out the individual errors from the Bolton game. But the performance at the Reebok was a bit insipid.

'We got in Middlesbrough's faces and the crowd were excellent. We got the breakthroughs and we held on to them. We defended stoutly.'

There had been little in the game until McSheffrey's inswinging 22nd-minute free-kick.

It carried little threat but Downing succeeded only in deflecting the ball past his keeper. Stephen Kelly redeemed himself after a rare blemish at Bolton three days earlier by clearing off the line after Birmingham keeper Maik Taylor missed Downing's freekick, Jeremie Aliadiere being denied a goal by the home defender.

Then Boro fell further behind as another example of Seb Larsson's excellent delivery was flicked on by Cameron Jerome at the near post for Forssell to score his fourth goal in eight starts by tapping home at the far post.

McLeish said: 'We need to wrap him in cotton wool. I've never seen anyone fire off as many shots as he does in training. He's a quality player.'

Taylor saved superbly from Tuncay Sanli midway through the second period. But that was rendered incidental in the last few seconds when McSheffrey was the victim of a clumsy Robert Huth challenge, dusting himself down to net from the spot.

Southgate said: 'I don't think we deserved anything. We were poor in the first-half. We didn't get out of the traps.

'I heard people use the phrase "we have turned a corner" after we beat Arsenal but I knew we hadn't.

'There's a tremendous amount of work still to be done. We have let ourselves down because 3-0 here is a poor result. We need to get ourselves back on track at Portsmouth.'

Birmingham: Maik Taylor, Kelly, Jaidi, Ridgewell, Queudrue, McSheffrey, Muamba, Johnson, Larsson, Jerome, Forssell. Subs: Doyle, O'Connor, Nafti, Djourou, De Ridder.

Middlesbrough: Schwarzer, Young, Wheater, Woodgate, Pogatetz, Boateng, Rochemback, Arca, Downing, Sanli, Aliadiere. Subs: Turnbull, Huth, Shawky, Lee, Johnson.

Referee: Mark Halsey (Lancashire)