Sheffield United's automatic promotion hopes suffered a significant blow after they were held at Birmingham.
Blues skipper Michael Morrison cancelled out Enda Stevens' opener to secure a 1-1 draw and dent the Blades' top-two charge.
They missed the chance to go back into the automatic promotion spots and now sit a point behind Leeds in the Sky Bet Championship with just five games left.
Dean Henderson saved well from Che Adams but Chris Wilder's side nearly snatched victory late on, only for David McGoldrick to nod over.
Birmingham, after their nine-point deduction threatened to drag them into a relegation battle, have taken four points from Leeds and the Blades in their last two games to sit 17th.
Despite the game's significance, the visitors struggled to get going and needed Henderson to rescue them after 19 minutes.
Gary Gardner's cross struck Martin Cranie and forced Henderson into a scrambling save at his near post.
Harlee Dean smashed over after half an hour but, out of the blue, it was United who took the lead seven minutes before the break.
Birmingham's victory over Leeds on Saturday did the Blades a favour and Lee Camp provided another helping hand when he was beaten by Stevens' opener.
Mark Duffy's strong run set Stevens scampering into the area and Camp let his fierce rising strike through his despairing dive.
But Birmingham levelled four minutes later when, from Connor Mahoney's corner, Gardner's header was blocked and Morrison stabbed in the rebound from eight yards.
Blues deserved their equaliser and Camp's smart low save stopped McGoldrick restoring United's lead eight minutes after the break.
Yet it was a rare second-half chance for United, who had lost just once in their last 12 games, as they relied on Henderson to keep them level.
First, after 62 minutes, the on-loan Manchester United goalkeeper turned over Adams' drive before saving low three minutes later to thwart substitute Jota.
United recovered and almost snatched victory but McGoldrick headed Oliver Norwood's corner over with two minutes left to leave the Blades' promotion hopes in the balance.