Two goals from substitute Lee McEvilly earned Cambridge a draw at Burton in the Blue Square Premier play-off semi-final first leg.
A Daryl Clare penalty gave the home side the lead and Darren Stride's header doubled their advantage.
McEvilly reduced the deficit from the penalty spot after Paul Hurst was deemed to have handled in the box.
The on-loan striker secured a draw for the visitors late on as he curled in a free kick from the edge of the area.
Burton had the better of the first half and thought they took the lead just after the interval, but John Brayford's headed goal was ruled out for a foul on Mark Albrighton.
The Brewers did take the lead on 66 minutes when Courtney Pitt brought down Andrew Corbett in the box and experienced striker Clare made no mistake from 12 yards.
Stride's header from Keith Gilroy's free-kick seemed to put the home side in control, but with 12 minutes remaining McEvilly gave Cambridge hope from the penalty spot.
McEvilly set up an intriguing second leg clash with as he netted his second directly from a free-kick.
Burton Albion: Poole, Brayford, James, Stride, Hurst, Corbett, Simpson, McGrath, Gilroy, Harrad, Clare. Subs: Deeney, Webster, Goodfellow, Austin, Williams.
Cambridge Utd: Potter, Morrison, Hatswell, Albrighton, Brown, Gleeson, Wolleaston, Carden, Reed, Vieira, Beesley. Subs: Farrell, Peters, Boylan, Pitt, McEvilly.
Att: 5,757
Ref: S Hooper (Swindon)
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