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.Relive Luton's draw with HuddersfieldSheff Utd v Nottm Forest previewVAR to be used in Championship play-off final
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.
VAR in the Championship?Nathan Jones and his Luton coaching staff appealed to the fourth official after Jerome appeared to be pulled down
This season's play-off final will see the video assistant referee used in the Championship for the first time.
Had it been operating in this game, the outcome might have been very different.
As well as two possible penalties in the first half, there could also have been one in the second when Bradley grappled with Sarr in the area and seemed to drag him down.
VAR might also have resulted in Luton's goal being disallowed as Harry Cornick, who was in an offside position, attempted to make contact with Naismith's delivery before Bradley directed the ball into the net from close range.
A number of managers in the second tier have argued for the introduction of VAR in the division, and would no doubt point to this match as an example of why.
Two teams defying the odds
Neither the Terriers nor Luton were rated among the promotion favourites at the start of season.
Regardless of what happens in the second leg, both clubs have made a mockery of those odds.
Huddersfield finished the regular season in third place and had won six of their previous seven matches before the trip to Bedfordshire.
They showed their quality while controlling possession in the second half against a determined Luton side, that has maintained a promotion challenge despite a limited budget and having been plagued by injury problems.
Nathan Jones' men will be no pushovers at the John Smith's Stadium, but Huddersfield will be pleased to begin their home leg on level terms.Huddersfield midfielder Duane Holmes was the standout player in the second half
Formation 3-1-4-227Ingram16BurkeSubstituted forHyltonat 80'minutes5Bradley4NaismithBooked at 57mins23LansburySubstituted forLockyerat 67'minutes2Bree22Campbell18Clark29Bell35JeromeSubstituted forSnodgrassat 89'minutes7Cornick
Formation 3-4-321Nicholls32Lees6Hogg23Sarr20TurtonSubstituted forÁvilaat 45'minutes37Russell8O'Brien3Toffolo24SinaniSubstituted forThomasat 85'minutes25WardSubstituted forRhodesat 71'minutesBooked at 90mins19Holmes
Match ends, Luton Town 1, Huddersfield Town 1.
Second Half ends, Luton Town 1, Huddersfield Town 1.
Foul by Jordan Rhodes (Huddersfield Town).
Tom Lockyer (Luton Town) wins a free kick in the defensive half.
Jordan Rhodes (Huddersfield Town) wins a free kick in the defensive half.
Foul by Kal Naismith (Luton Town).
Jordan Rhodes (Huddersfield Town) is shown the yellow card for a bad foul.
Foul by Jordan Rhodes (Huddersfield Town).
James Bree (Luton Town) wins a free kick in the defensive half.
Substitution, Luton Town. Robert Snodgrass replaces Cameron Jerome.
Corner, Huddersfield Town. Conceded by Jordan Clark.
Corner, Huddersfield Town. Conceded by Sonny Bradley.
Attempt blocked. Pipa (Huddersfield Town) right footed shot from outside the box is blocked. Assisted by Duane Holmes.
Corner, Luton Town. Conceded by Naby Sarr.
Attempt missed. Tom Lockyer (Luton Town) header from the centre of the box is too high. Assisted by Kal Naismith with a cross.
Substitution, Huddersfield Town. Sorba Thomas replaces Danel Sinani.
Attempt missed. Jordan Clark (Luton Town) right footed shot from outside the box is too high. Assisted by Amari'i Bell.
Substitution, Luton Town. Danny Hylton replaces Reece Burke because of an injury.
Attempt missed. Tom Lees (Huddersfield Town) header from the centre of the box misses to the right. Assisted by Danel Sinani with a cross following a corner.
Corner, Huddersfield Town. Conceded by Reece Burke.