Despite fielding many Premier League regulars, the much-fancied Danes were given a tough workout in Group D.
Both sides had goals ruled out for offside, while Denmark's Andreas Cornelius somehow missed from a yard.
There was 95th-minute drama when referee Cesar Ramos checked the pitchside monitor over a potential Denmark penalty for handball, only to stick with his original decision and award a goal-kick.
One of the pre-tournament favourites, Denmark will need to find some form if they are to qualify from a group that also includes World Cup holders France.
Watch: Tunisia hold Denmark to goalless draw in opener
Denmark 0-0 Tunisia
These are the highlights from the match as Tunisia hold Denmark to a frustrating goalless draw in the Group C opener at the Fifa World Cup.
Post update
Denmark 0-0 Tunisia
Seeing that potential handball again from Yassine Meriah. He has jumped, trying to defend a corner from Christian Eriksen. The ball hits his right arm at the side of his body, deflects off his chest and then hits the left arm, with his elbow bent but still tight to his body.
Denmark had wanted a handball earlier in the game and that wasn't given so referee Cesar Arturo Ramos gets some praise for consistency.
'Tunisia were the better team'
FT: Denmark 0-0 Tunisia
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
It was a very good 0-0, plenty of incidents and interesting mistakes as well. Dahmen nearly threw one in at the end but he was really really good
Christian Eriksen looked dangerous from set pieces.
But you just love watching Tunisia play because they came in as underdogs but they came out as the better team. But also, the most exciting team, the more entertaining team.
On top of that, Laidouni. I am watching them next time they play for him and nothing else. I'm going to watch him because he is a joy, interesting and exciting and he can play a bit.
Tunisia deserved the point and maybe just a bit more.
FULL-TIME
Denmark 0-0 Tunisia
It's all over. Tunisia, 30th in the world rankings, earn a brilliant point against a Denmark side 10th in the world.
Denmark will feel they should've had a penalty in injury time when the ball hit the arm of Yassine Meriah. Referee Cesar Arturo Ramos went to check the incident on a pitchside monitor.
Normally we've come to expect that the decision will be changed, but he stuck with his original decision, said 'no penalty' and it's a point apiece.
Getty ImagesCopyright: Getty Images
Post update
Into the 98th minute...
Post update
Into the sixth minute of additional time. We were only due five before that VAR drama.
'Referee has got that right'
Denmark 0-0 Tunisia
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
No penalty there, the referee has got that right. It came off his chest and then hit his arm. What a horrible, unfair end to the game that would have been if it had been given. The referee has had a very good game.
No penalty
Denmark 0-0 Tunisia
The referee goes to the pitchside monitor and Cesar Arturo Ramos watches it but sticks with his on-field decision.
The ball had hit the arm of Yassine Meriah but Denmark don't get a penalty.
That's not the last we've heard of that one.
Drama late on.
Post update
Denmark want a penalty after a header comes in from Christian Eriksen's corner.
We have a VAR check. This could be heartbreak for Tunisia.
Post update
Denmark 0-0 Tunisia
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
It's going to be a long five minutes for both sets of players because of the pace of the game. It's just swinging back in Denmark's favour at the moment, I suspect they'll get one more big chance before the game ends.
Post update
Denmark 0-0 Tunisia
Tunisia goalkeeper Aymen Dahmen gets his hands to the ball after a Denmark long throw momentarily caused a bit of panic.
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Liam: With the upset of Argentina this morning and now looking like Denmark being held by Tunisia could we see France defeated by Australia later? The beautiful game!
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Denmark 0-0 Tunisia
Five minutes of injury time for either side to find a winner.
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Denmark 0-0 Tunisia
There have been 14 shots at goal following corners in this game, already the most in any World Cup game on record (1966 onwards).
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Denmark 0-0 Tunisia
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
The referee has handled this game quite well because right at the start of the game, there were a lot of Tunisia players throwing themselves about.
Getty ImagesCopyright: Getty Images
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Denmark 0-0 Tunisia
The hugely-influential Aissa Laidouni has been taken off for the last few minutes and he has given absolutely everything.
As you'd expect he's roaring on the fans, the substitutes, the rest of the coaching staff and anyone else who gets in his way as he comes off the pitch. Leader.
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Via WhatsApp - 03301231826
Terry: This World Cup is showing that team spirit can be far more important than having a plethora of household names.
Live Reporting
Michael Emons
All times stated are UK
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Getty ImagesCopyright: Getty Images
Latest PostThanks and goodbye
FT: Denmark 0-0 Tunisia
That's all for this live so thanks for joining us.
The football comes thick and fast in the opening days of a World Cup so we're already in position with the live coverage of the next one.
So to watch, listen to and read coverage of Mexico v Poland, head this way.
Watch: 'He really has to score!' Cornelius misses huge chance for Denmark
FT: Denmark 0-0 Tunisia
Andreas Cornelius, the ex-Cardiff City striker, will be left wondering just how he didn't score with this chance.
Denmark held by vibrant Tunisia - read the report
Denmark 0-0 Tunisia
Joe Bradshaw
BBC Sport
Denmark were held to a draw by Tunisia in their World Cup opener in a raucous atmosphere at the Education City Stadium in Al Rayyan.
Despite fielding many Premier League regulars, the much-fancied Danes were given a tough workout in Group D.
Both sides had goals ruled out for offside, while Denmark's Andreas Cornelius somehow missed from a yard.
There was 95th-minute drama when referee Cesar Ramos checked the pitchside monitor over a potential Denmark penalty for handball, only to stick with his original decision and award a goal-kick.
One of the pre-tournament favourites, Denmark will need to find some form if they are to qualify from a group that also includes World Cup holders France.
Watch: Tunisia hold Denmark to goalless draw in opener
Denmark 0-0 Tunisia
These are the highlights from the match as Tunisia hold Denmark to a frustrating goalless draw in the Group C opener at the Fifa World Cup.
Post update
Denmark 0-0 Tunisia
Seeing that potential handball again from Yassine Meriah. He has jumped, trying to defend a corner from Christian Eriksen. The ball hits his right arm at the side of his body, deflects off his chest and then hits the left arm, with his elbow bent but still tight to his body.
Denmark had wanted a handball earlier in the game and that wasn't given so referee Cesar Arturo Ramos gets some praise for consistency.
'Tunisia were the better team'
FT: Denmark 0-0 Tunisia
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
It was a very good 0-0, plenty of incidents and interesting mistakes as well. Dahmen nearly threw one in at the end but he was really really good
Christian Eriksen looked dangerous from set pieces.
But you just love watching Tunisia play because they came in as underdogs but they came out as the better team. But also, the most exciting team, the more entertaining team.
On top of that, Laidouni. I am watching them next time they play for him and nothing else. I'm going to watch him because he is a joy, interesting and exciting and he can play a bit.
Tunisia deserved the point and maybe just a bit more.
FULL-TIME
Denmark 0-0 Tunisia
It's all over. Tunisia, 30th in the world rankings, earn a brilliant point against a Denmark side 10th in the world.
Denmark will feel they should've had a penalty in injury time when the ball hit the arm of Yassine Meriah. Referee Cesar Arturo Ramos went to check the incident on a pitchside monitor.
Normally we've come to expect that the decision will be changed, but he stuck with his original decision, said 'no penalty' and it's a point apiece.
Post update
Into the 98th minute...
Post update
Into the sixth minute of additional time. We were only due five before that VAR drama.
'Referee has got that right'
Denmark 0-0 Tunisia
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
No penalty there, the referee has got that right. It came off his chest and then hit his arm. What a horrible, unfair end to the game that would have been if it had been given. The referee has had a very good game.
No penalty
Denmark 0-0 Tunisia
The referee goes to the pitchside monitor and Cesar Arturo Ramos watches it but sticks with his on-field decision.
The ball had hit the arm of Yassine Meriah but Denmark don't get a penalty.
That's not the last we've heard of that one.
Drama late on.
Post update
Denmark want a penalty after a header comes in from Christian Eriksen's corner.
We have a VAR check. This could be heartbreak for Tunisia.
Post update
Denmark 0-0 Tunisia
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
It's going to be a long five minutes for both sets of players because of the pace of the game. It's just swinging back in Denmark's favour at the moment, I suspect they'll get one more big chance before the game ends.
Post update
Denmark 0-0 Tunisia
Tunisia goalkeeper Aymen Dahmen gets his hands to the ball after a Denmark long throw momentarily caused a bit of panic.
Get Involved
Via WhatsApp - 03301231826
Liam: With the upset of Argentina this morning and now looking like Denmark being held by Tunisia could we see France defeated by Australia later? The beautiful game!
Post update
Denmark 0-0 Tunisia
Five minutes of injury time for either side to find a winner.
Post update
Denmark 0-0 Tunisia
There have been 14 shots at goal following corners in this game, already the most in any World Cup game on record (1966 onwards).
Post update
Denmark 0-0 Tunisia
Pat Nevin
Former Scotland winger on BBC Radio 5 Live
The referee has handled this game quite well because right at the start of the game, there were a lot of Tunisia players throwing themselves about.
Post update
Denmark 0-0 Tunisia
The hugely-influential Aissa Laidouni has been taken off for the last few minutes and he has given absolutely everything.
As you'd expect he's roaring on the fans, the substitutes, the rest of the coaching staff and anyone else who gets in his way as he comes off the pitch. Leader.
Get Involved
Via WhatsApp - 03301231826
Terry: This World Cup is showing that team spirit can be far more important than having a plethora of household names.