Donald Oluoch:, external Another extraordinary start to the Argentina-Nigeria second half. Got to love football.

Chris Gilbert:, external Argentina's attack looks great with Messi, and they could go far, but their defence looks suspect, which may be a problem.

And the corner is costly as Argentina retake the lead! It's messy defending as Ezequiel Garay wins the header which hits his team-mate Marcos Rojo on the knee and skips into the net.

Another thriller...

Image source, Getty Images

Have some of that! Great hit from Angel Di Maria thrashes in a powerful shot from range and it's turned away for a corner.

John McEnerney:, external Barcelona fans won't be happy with Messi, he really didn't put the effort in last season! Saving himself for this, Rivaldo did same in 02!

Owain Morgan:, external Backing Benzema to overtake both Messi and Neymar with two goals against Ecuador later.

Matt Donnelly:, external This is Messi's World Cup but regardless of what happens the joy people get from watching him has cemented his legend status.

Former Premier League striker Jason Roberts
BBC Radio 5 live, Porto Alegre

"Musa has done a Messi and scored twice. Nigeria will not give up on this game. What a cracker."

Image source, Getty Images

Anything Messi can do, Musa can match!

Ahmed Musa has his second of the game, and it's another excellent one, He plays a one-two with Emmanuel Emenike, runs into the penalty area and clips it into the corner. Easily done but brilliantly taken.

Image source, AFP

Former Premier League striker Jason Roberts
BBC Radio 5 live, Porto Alegre

"Other players have made previous World Cups their own. Lionel Messi can make the 2014 World Cup his."

You can listen to live commentary on BBC Radio 5 live by clicking on the 'Highlights' tab above.

Just a recap then, a big win for Iran could still take them through ahead of Nigeria.

...and back in play in Porto Alegre too.

We've kicked-off...

Iran have had only four shots on goal in the whole tournament. Got to raise it...

Richard:, external Musa's goal is much better than either of Messi's but, as usual, no one can see past the Argentine.

Bizzle from London on text: Come on Iran!!! Start pushing and attacking. This match is worth so much more to you than this!

Image source, Getty Images

Ezequiel Lavezzi showed off some wonderful tattoos when he came on to replace Sergio Aguero - including this beauty of Kevin Keegan.

Or maybe it's Diego Maradona...

Sandip Bhogal on Facebook:, external Messi's performance not been great but man gotta admit he's still deadly.

Spiros Kele:, external Bad keeping. Messi is good against small teams but with good teams he disappears.

Nigeria showed enough in that first half to suggest that they could get back into the game though. Goalscorer Ahmed Musa and Emmanuel Emenike have been dangerous - they could test France in the next round too, if that is how it all pans out.

Steven Jerjian:, external Even the great teams need that special player to carry them to glory. Getting the feeling this could be Messi's World Cup.

Jack Willows:, external The world is running out of ways to describe Lionel Messi. Genius.

Daniel Woodley:, external Messi is a genius. I could watch a camera fixed on him throughout the full 90 minutes of football.

The race for the golden boot is up to four - and it's Neymar and Lionel Messi leading the way. A marketing man's dream.

Image source, AFP

Image source, AFP

Steve Claridge, BBC Radio 5 live

"You would never believe Iran have to win this to have a chance of going through. They don't look like a team that truly believe they can win."

Lionel Messi has long since reserved his place in the hall of fame, but if he keeps on going in this touch of form he can select a spot in the main hall, by the window alongside Pele and Diego Maradona.

The best of our time? Cristiano Ronaldo says no. I'm not sure what I say...