The Championship play-off semi-final between Luton and Huddersfield is finely poised after the first leg ended in a draw at Kenilworth Road.
Danel Sinani put Huddersfield ahead before Sonny Bradley equalised.
Both sides had appeals for a penalty turned down in an exciting encounter.
They will meet again in Monday's second leg, with the winner facing Nottingham Forest or Sheffield United at Wembley on Sunday, 29 May for a place in the Premier League.
Huddersfield should arguably have been awarded a spot-kick in the opening 10 seconds when Harry Toffolo was barged over by James Bree while trying to get to Ollie Turton's cross.
The visitors then had to absorb a spell of pressure - but went ahead on the counter-attack after Luton were caught out by Toffolo's ball forward.
Sinani, on loan from Norwich, capitalised by taking on Bradley and firing past keeper Matt Ingram at his near post.
Skipper Bradley hauled Luton level on the half-hour mark by nudging home Kal Naismith's left-wing free-kick.
And Luton then had a penalty appeal of their own waved away by referee Robert Jones when Cameron Jerome burst through on goal and went down after tangling with Naby Sarr.
Huddersfield dominated possession as the Hatters tired in the second half, but both struggled to create clear-cut chances.