Birmingham ended Matt Bloomfield's unbeaten start at Oxford to continue their new year revival as they target the Championship play-offs.

U's defender Myles Peart-Harris got the final touch to Paik Seung-Ho's free-kick for the first goal before Marvin Ducksch fired home to stretch the Blues' unbeaten run to six games.

Ducksch's red-hot form mirrors his team's in January and the German striker has five goals in his last six games and eight in total for the season.

Ambitious Birmingham have reportedly spent £15m so far in the winter transfer window, strengthening Chris Davies' squad, and they are now five points off the play-offs.

They believe they can get in the mix for a top-six spot and are transformed since their 3-0 New Year's Day defeat at Watford.

Oxford, meanwhile, have slipped five points below the safety line after Bloomfield's first loss in his fourth game as their new manager.

The home side paraded new signing Christ Makosso at the Kassam Stadium before kick-off, the Congo defender having joined on loan from Luton for the rest of the season.

The U's made a positive start as Matt Phillips and Peart-Harris went close, but they undid all their good early work when they conceded a soft goal to gift Birmingham the lead on 23 minutes.

There was some questionable goalkeeping from Jamie Cummings as Paik's free-kick rebounded off Peart-Harris and into his own net.

Birmingham should have doubled their lead when Jay Stansfield broke through butIbrahim Osman could not apply the final touch to his pass, instead colliding with the post.

The visitors made no mistake, though, on 66 minutes when debutant Carlos Vicente, who only joined from Alaves four days ago, flicked the ball into the path of Ducksch and he swept it into the corner from the edge of the box.

They are next in action at home to Leicester City next Saturday, while Oxford have a chance to atone when they go to Sheffield United on Tuesday evening.

Oxford manager Matt Bloomfield told BBC Radio Oxford:

"I always try and speak as honestly as I can after games and last week we were worthy winners, but today it wasn't to be.

"Our levels weren't quite at the level required to win the game, playing against incredibly good opposition, who've spent so much money on their squad. Our intensity needed to be at the top and we just didn't quite get there today.

"For their second goal, we were actually in possession, we're breaking out, we gave the ball away and the next thing you know, it's in the back of our net. Two-nil put a bit of a pin in us because I felt we were starting to build a bit of momentum.

"It's a deeply frustrating end, but we don't get too low. It's the first defeat, there's going to be a rollercoaster between now and the end of the season and we have to make sure that every day we come in ready to work and we keep moving forward."

Birmingham boss Chris Davies told BBC WM:

"Obviously. I'm really pleased with the win, but I was thinking before the game that I wanted us to play well, I wanted us to have that level of control in the match.

"I emphasised that during the week and I think you could see that today. There was a good calmness and a good patience to our game. I think we had a good balance to our possession and that gave us a level of control, which I think was massive in winning the match.

"This calendar year we've looked more of a team. That's the first thing I've been emphasising to the players – you've got to be a team, you've got to work hard for each other and that gives you a chance of winning games in this league.

"We've looked like that in the last few games. Away from home was the question mark, but we've gone and done that. Here again, another clean sheet and a couple of goals and that's really good for the confidence."