Andy O'Brien's own goal in stoppage-time denied Leeds a return to the top two in the npower Championship as visitors Portsmouth twice fought back from two goals down to draw 3-3.
Leeds centre-half O'Brien deflected Pompey substitute Nadir Ciftci's 93rd-minute cross into his own net for his second own goal of the afternoon to hand the visitors an unlikely point.
Simon Grayson's side extended their unbeaten run to 11 matches, but failed to capitalise on Cardiff's 4-1 defeat at Watford and closed out 2010 in fourth place in the table.
Max Gradel struck his fifth goal in four matches and skipper Jonny Howson slammed home his eighth of the season inside the opening 10 minutes to set Leeds on their way in front of a crowd of 31,556, but Portsmouth, who had beaten promotion-chasers Swansea and Norwich in their last two away games, hit back in the first half through David Nugent's superb strike.
Bradley Johnson gave Leeds another two-goal cushion in the 62nd minute, but Leeds defender O'Brien deflected Richard Hughes' shot beyond his goalkeeper Kasper Schmeichel for his first own goal within 60 seconds to reduce the deficit again.
Leeds had vociferous appeals for a late penalty turned down by Lancashire referee David Webb and were then denied three points three minutes into time added on when O'Brien again deflected into his own net.