Sheffield United made light work of 10-man Birmingham City to move seven points clear of the Championship relegation zone.

The home side took an early lead when Tyler Bindon rose unchallenged to head Gustavo Hamer's corner in before Blues had Tommy Doyle sent off for a rash challenge on Hamer on the halfway line.

Hamer then capitalised on a dreadful backpass from Keshi Anderson to make it 2-0 after 30 minutes.

Patrick Bamford, who looked to be marginally offside, deflected Oli Arblaster's effort in from close range to wrap up the points with over 30 minutes left to play.

Birmingham are now four games without a win and managed just one shot on target in this comprehensive loss.

The Blades, who had been poor in their 2-0 defeat at West Brom last week, move up to 18th and are nine points off the top six.

Chris Wilder had not hidden his displeasure at his side's efforts in last week's reverse at the Baggies, calling them "lacklustre".

He made five alterations from that game and one of them, defender Bindon, made a near-instant impact when he headed over Ryan Allsop in the away goal after just five minutes.

Things got worse for the away side when former Blades loanee Doyle sprinted in to an ill-advised challenge with Hamer in front of the dugouts and took his man out to see red for the first time in his career.

Another miserable away day for Birmingham, who have now lost seven of their 11 games this season, was compounded when they got caught trying to play out from the back. Anderson attempted to play the ball back to Allsop but Hamer stole in and beat the keeper to it before lashing home.

With the result already threatening to get out of hand Chris Davies took booked winger Anderson off immediately for midfielder Marc Leonard to try and shore things up, although they still conceded a third.

The Blades are keen to tie striker Bamford up to a longer deal, with his current contract expiring next month, and the former Leeds man scored his third goal in seven appearances to add some deserved gloss to the scoreline, albeit he appeared to have been offside when Arblaster had the initial shot.

Sheffield United boss Chris Wilder told BBC Radio Sheffield:

"It's not about me wanting a response it was about them wanting a response from themselves, within. The narrative all week was a strong one, Friday night was unacceptable and I didn't enjoy it at all.

"The players had an opportunity to put it right and they did. The start was great, the intensity of our play. The press we got absolutely spot on. We smothered them and didn't allow them to get a foothold in the game.

"Maybe the frustration of that was the reason that Tommy got sent off. Yes of course it was an easier afternoon with 11 v 10 but still delighted with the way we approached it.

"We didn't give them any opportunities. It was a really good afternoon."

Birmingham City boss Chris Davies told BBC Radio WM:

"It was quite the opposite of everything we had been talking about and working on.

"The whole week's work was building up to this fixture and we didn't start quick enough and conceded an extremely soft goal from a corner, one of the worst we've conceded.

"The challenge was a red card, I think you'd be lying to say it wasn't. It was reckless and Tommy has owned that and accepted responsibility. It's not the kind of team that I want to be.

"If our away form has been this poor our home form needs to be so good and that's unfortunately the position we're in now. The good news is we are better at home and we need to take that with us moving forward."

Birmingham will look for some home comfort when they welcome Derby on Boxing Day (12:30 GMT), while the Blades are away at Wrexham later on that afternoon (17:30 GMT).