Another chance for Mitchell Duke but his header is straight at the keeper. I think he was surprised at the chance but it came to him at speed. Relief for Tunisia.

Vicki Sparks
BBC commentator

The block from Harry Souttar was outstanding. A goal-saving block preserves Australia lead.

Danny Murphy
Former England midfielder on BBC One

Talk about putting your body on the line. Brilliant block from Souttar.

Although it's a wonderful block, he's got to score. What an opportunity for Mohamed Drager.

Magnificent by Harry Soutter.

Tunisia look certain to equalise through Mohamed Drager after a quick throw-in but Souttar saves his side with a brilliant block.

Danny Murphy
Former England midfielder on BBC One

That is the first little bit we've seen from Youssef Msakni, he played well against Denmark but we haven't really seen him in this game.

This game has been peppered with free-kicks. Mohamed Drager is receiving treatment after accidentally being caught in the face by Craig Goodwin's boot.

Moments earlier Youssef Msakni found space inside the Socceroos box but his attempt was blocked.

Danny Murphy
Former England midfielder on BBC One

Australia have been really good at breaking up those little moves. Just when Tunisia start to get a bit of rhythm, someone bites into a tackle.

Another replay of Mitchell Duke's goal.

It just gets better and better with each watch. A really beautiful header.

Karen Bardsley
Former England and Manchester City goalkeeper on BBC Radio 5 Live

I think Australia are going to have to start managing the physicality of this game. They don’t want to get carried away and need to calm down a little in terms of their decision-making.

Tunisia will thrive if they win free-kicks in dangerous areas.

Image source, Getty Images

Mitchell Duke is the second Australian player to score a header at the World Cup, after Tim Cahill who did so twice (v Serbia in 2010 and Chile in 2014).

Corner to Australia. It's not the best but it reaches Jackson Irvine who manages to get some sort of contact on it. Wide.

Danny Murphy
Former England midfielder on BBC One

Better from Tunisia, a bit more urgency. That's what they need.

You can see them squeezing up the pitch a bit more now as well, exactly what they need to do.

That goal has really shaken things up in Group D. Australia have gone from bottom to second. Denmark play leaders and defending world champions France later today.

Emma Sanders
BBC Sport at Al Janoub Stadium

Such a huge goal for Australia. They have been the better side, despite not creating much, and that was a stunning header from Mitchell Duke. He had so much to do. A few Aussies in the media box stood up in celebration as it seemed to come out of nowhere. The players all ran to the corner flag, with the substitutes sprinting down the touchline and patting Duke on his head relentlessly.

Danny Murphy
Former England midfielder on BBC One

A bit of frustration from Laidouni after conceding the goal. It's the right decision, a silly tackle.

It's another perfect start to a game from Australia, though. They've done so much right, just like they did in the first game. Can they maintain this?

This is not going to plan for Tunisia. They haven't started well and Aissa Laidouni is booked for a lunge on Craig Goodwin. Frustration is creeping in.

Mitchell Duke's header is the 50th goal of this World Cup.

Karen Bardsley
Former England and Manchester City goalkeeper on BBC Radio 5 Live

Again, Australia exposed the narrowness of the Tunisian back four and what a header it was from Duke.

Australia will take huge confidence from the way that goal was scored.

Vicki Sparks
BBC commentator

Image source, Getty Images

The breakthrough that Australia so desired!