Mexico got their joint-home World Cup off to the perfect start with a 2-0 opening match win over nine-man South Africa - in a game that had THREE red cards.

It was, however, a World Cup debut to forget for South Africa midfielder Yaya Sithole at a raucous Azteca Stadium, who was at fault for Mexico's first as he gave away possession for Julian Quinones to strike home after nine minutes.

Then the midfielder was given a straight red card in the second half as he brought down Bryan Gutierrez through on goal, with referee Wilton Sampaio taking no time in giving him his marching orders.

In truth, Mexico should have been out of sight even before the red card. Raul Jimenez was denied twice by South Africa goalkeeper Ronwen Williams, while Quinones struck the post in a dominant first half for Mexico, as Bafana Bafana barely threatened.

But with the nerves entering the Azteca, Raul Jimenez put them to bed as he headed home Roberto Alvarado's cross at the back post for his first ever World Cup goal. Given everything he's been through with his serious head injury in 2020, there was no surprise to see tears in his eyes.

There was even room for VAR to get involved as the video referee spotted South Africa substitute Thembo Zwane swiping at Alvarado's face when fighting for the ball. In the first controversial call of the tournament, referee Wilton Sampaio sent Zwane off too.

Then Mexico defender Cesar Montes was controversially given his marching orders by Sampaio for stopping a South Africa counter on the edge of the box. Despite Khalisu Madau having a long way to go to goal, the Mexico defender was sent down the tunnel - even after VAR checked it.

The key moments from an eventful Mexico City opener...

Analysis: The new normal? New rules in play at World Cup opener

Sky Sports' Sam Blitz:

There are lots of trends and talking points from this opening match, right from the moment we saw the Azteca Stadium for the first time.

Loud boos for the United States flag will raise questions about anti-American sentiment when matches are played in Canada and Mexico.

Speaking of atmosphere, how England will fare at a loud and tricky Azteca Stadium if they meet Mexico in the last 16 round, as projected, could be a conversation to have from this opening game.

But what stands out is the new rules in play at the World Cup. There is a clear desire from officials to speed the game along and reduce time-wasting.

In first-half stoppage time, referee Sampaio hurried Mexico along and brought in the new 'five-second rule' - counting the time down on his hand when he felt the co-hosts were taking too long.

Substitutions are much quicker too, with every single player sprinting off the pitch when taken off. If players take longer than 10 seconds, the outgoing player is booked.

Will these new rules create a quicker game? The jury is still out. This match also saw the three-minute water break in the middle of each half rolled out - with the PA system taking the opportunity to play music out of the speakers. It's new, but it won't sit well with everyone.

The time is still added on in stoppage time - so there's not exactly a loss of time. But whether teams can recover the flow of the game after breaks will be interesting to see.

With the new guidance on holding at corners still to be judged, and VAR hasn't got off to the best start so far after that controversial Zwane sending off, the biggest World Cup ever is set to see a new form of football to get used to.

What the result means...

In pictures: The World Cup opening ceremony

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