Match ends, Denmark 1, Australia 1.
Denmark manager Age Hareide said video assistant referees are taking the "charm" out of the World Cup after Australia scored a debatable penalty to keep their last-16 hopes alive.
Australia cancelled out Christian Eriksen's fine opener when Mile Jedinak converted from the spot after Yussuf Poulsen's handball in the area was penalised by VAR.
The ball struck Poulsen on his trailing arm as he contested a header with Mathew Leckie.
"I do believe it was a penalty but the whole issue with VAR is that there are people somewhere in Russia deciding to look at this situation because it looks like a penalty," said Hareide.
"That is OK but there were other situations in the match where they should have stopped it to look at what actually happened but they are not doing that, so who decides?
"Is it the referee on the pitch or someone watching in a dark room somewhere else?
"To me, it was probably correct but it does remove a bit of the charm of football to have such a precise system.
"I don't know how it will work out for football in the long run."
In an absorbing encounter, Aston Villa's Jedinak sent Kasper Schmeichel the wrong way for his second goal of the tournament after Eriksen had put Denmark ahead with a super finish following Nicolai Jorgensen's clever lay-off.
Aaron Mooy went close from distance for Australia before Denmark's Pione Sisto was left holding his head after a curling shot from outside the area flashed just wide.
The result means Denmark need a point in their final Group C match against France to be certain of reach the knockout stage, while Australia can still qualify but must beat Peru to have any hope of extending their stay in Russia.
Eriksen stunner leaves Denmark well placed
Denmark have not reached the last 16 since 2002 but Hareide's side are in a strong position to advance in Russia after following up victory over Peru with a hard-earned point.
Poulsen, who has now conceded penalties in successive games in Russia, complained that there was little he could do to get his hand out of the way of Leckie's header.
His frustration increased as he was also booked for the incident, which means he will miss the final group game.
Denmark failed to build on a strong start handed to them by a sublime finish from Tottenham playmaker Eriksen, who has now had a hand in 18 goals in his past 15 appearances for his country - 13 goals and five assists.
Jorgensen could not find the target with a free header after sneaking behind Australia's defence while Sisto wasted a further two chances.
Denmark may need to be more ruthless in front of goal if they are to earn the point against France that would seal their progression to the last 16.
Gritty Australia stay alive
Having lost their opening group game to France, Australia needed a positive result to avoid an early exit.
They still have their work cut out to advance beyond the group stage but Bert van Marwijk's side demonstrated in Samara that they are up for the challenge.
Socceroos captain Jedinak is proving to be as vital to Australia as Cristiano Ronaldo is to Portugal.
Australia's last three goals at a World Cup have all been penalties scored by Jedinak, who also netted a further 10 times in qualifying.
They lost forward Andrew Nabbout to a suspected dislocated shoulder but 19-year-old substitute Daniel Arzani, the youngest player at the tournament, caught the eye as Australia produced a strong finish.
Man of the match - Christian Eriksen (Denmark)
'We gave the ball away too much' - the managers
Denmark boss Age Hareide: "My players looked tired. You could see them tiring as the match went on.
"We tried to get our substitutes on to inject some energy but our game was restless. We lost the ball too often, faced too many counter-attacks and had to do too much running.
"But that's the World Cup - it's very tough and that's just the way it is.
"Australia are a good side, well organised, and France were lucky to beat them 2-1. So we knew it was going to be tough. The level of effort from my team was good. We just gave the ball away too often and made too many wrong choices."
Australia boss Bert van Marwijk: "I feel we should have won. It's like against France. I'm disappointed and proud, and feel we deserved more.
" I honestly think we've deserved four points from these two games. So I'm very disappointed.
"It is just the last piece of the puzzle we are missing. Now we must concentrate on Peru. The rest, in terms of whether we can qualify, we cannot influence."
Five matches without a World Cup win - the stats
- Despite a battling point, Australia have failed to win any of their past five World Cup matches (D1 L4), their joint-longest winless run in the competition.
- Denmark's Yussuf Poulsen is the first player to concede two penalties in a single World Cup since Milan Dudic for Serbia in 2006.
- Australia have failed to keep a clean sheet in each of their last 12 World Cup games, the longest current run in the competition alongside Saudi Arabia.
- Mile Jedinak's penalty for Australia ended a run of nine hours and 31 minutes without conceding at international level for Denmark's goalkeeper Kasper Schmeichel (571 minutes).
- 31% of goals scored by Australia at the World Cup have come from the penalty spot (four out of 13), the highest ratio among any of the teams to have scored at least 10 goals in the competition.
- Australia defender Mark Milligan completed 85 passes in this match - a record for an Australian player in a single game at a World Cup tournament.
Denmark next face France in Moscow's Luzhniki Stadium on 26 June (15:00 BST), the same time that Australia face Peru in Sochi.
- 17Stryger Larsen
- 20PoulsenBooked at 37minsSubstituted forBraithwaiteat 59'minutes
- 23SistoBooked at 84mins
- 9N JørgensenSubstituted forCorneliusat 68'minutes
- 13M Jorgensen
- 10KruseSubstituted forArzaniat 68'minutes
- 23RogicSubstituted forIrvineat 82'minutes
- 11NabboutSubstituted forJuricat 75'minutes
- Antonio Miguel Mateu Lahoz
- Shots on Target
Second Half ends, Denmark 1, Australia 1.
Offside, Denmark. Jens Stryger Larsen tries a through ball, but Martin Braithwaite is caught offside.
Attempt saved. Martin Braithwaite (Denmark) left footed shot from the left side of the box is saved in the top centre of the goal. Assisted by Christian Eriksen with a cross.
Corner, Denmark. Conceded by Aziz Behich.
Foul by Mile Jedinak (Australia).
Andreas Cornelius (Denmark) wins a free kick in the defensive half.
Attempt missed. Christian Eriksen (Denmark) right footed shot from outside the box misses to the left.
Attempt saved. Mathew Leckie (Australia) left footed shot from the centre of the box is saved in the bottom left corner. Assisted by Jackson Irvine with a cross.
Attempt saved. Daniel Arzani (Australia) right footed shot from the left side of the box is saved in the top centre of the goal. Assisted by Aziz Behich.
Pione Sisto (Denmark) is shown the yellow card.
Jackson Irvine (Australia) wins a free kick in the defensive half.
Foul by Thomas Delaney (Denmark).
Substitution, Australia. Jackson Irvine replaces Tomas Rogic.
Aziz Behich (Australia) wins a free kick in the defensive half.
Foul by Martin Braithwaite (Denmark).
Attempt blocked. Mathew Leckie (Australia) left footed shot from the right side of the box is blocked. Assisted by Tomi Juric.
Substitution, Australia. Tomi Juric replaces Andrew Nabbout because of an injury.
Delay over. They are ready to continue.
Delay in match Andrew Nabbout (Australia) because of an injury.