Birmingham City were beaten by two goals of Premier League quality as Tony Mowbray’s Sunderland won at St Andrew’s.

Manchester United winger Diallo then scored a superb, curling second four minutes into the second half to seemingly seal Blues’ first home defeat since August.

Substitute Lukas Jutkiewicz gave Blues hope on 78 minutes with his first goal in almost a year, but Sunderland survived late home pressure, including seven minutes of added time.

That was enough to earn Mowbray’s men a second straight away win on the former West Brom and Coventry boss’ return to the Midlands to lift Sunderland into the top half of the Championship table, within a point of John Eustace’s 10th-placed Blues.

Blues wasted a great early chance when skipper Troy Deeney’s header bounced back off the angle of the left upright and crossbar – and they were made to pay when Sunderland went in front.

Diallo looked like he had been halted on the edge of the penalty area, but he powered himself back off one knee to twist himself out of the tackle, spread the ball wide to Simms on the right and the distracted Blues defence were caught flatfooted as the big striker strode on into the box to arrow home a low right-foot shot.

Blues then blew another great chance when top scorer Scott Hogan was denied by Sunderland keeper Anthony Patterson in a one-on-one just before the break.

Soon after the restart the visitors’ lead was doubled when Diallo stole into the right side of the Blues box and, just when he seemed to be closed down, he unleashed a superb left-foot curler which dipped just inside John Ruddy’s right post.

Jutkiewicz’s introduction on 59 minutes in a triple substitution that also brought on George Hall and Tahith Chong and ended 17-year-old Jobe Bellingham’s evening on his first start, was always liable to have an effect.

But it brought only one goal as Jutkiewicz steered into the far corner after Bailey Wright missed his kick and, despite somehow surviving one incredible double escape in a frantic scramble, the visitors hung on.