We've got plenty of your questions coming in for BBC Sport's football tactics correspondent Umir Irfan - he's frantically typing away with his answers now.

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We've already posted the highlights a couple of times and they are in the key points at the top of this page too.

But it's no bother getting them to you again!

Image source, Reuters

Raul Jimenez's goal was the 46th for his country in his 125th appearance, moving him joint second in Mexico's list of goalscorers, behind only Javier Hernandez on 52.

Even when the game started, Jimenez was breaking new ground in his career.

He had previously made six substitute appearances in World Cup finals - one in the 2014 tournament, two in 2018 and on three occasions in 2022.

But, in his first World Cup start, he almost made an immediate impact, having a powerful half-volley superbly saved by South Africa's Ronwen Williams in the fourth minute.

Jimenez, who earlier this week completed a move from Fulham to former club Wolves, sealed the victory in the 67th victory to ensure co-hosts Mexico made a winning start.

Former England defender Gary Neville, speaking on ITV, said: "That is likely to be the greatest moment of his life from a football perspective, scoring in front of 80,000 in that stadium, in his home country. It is a great moment for him."

Ex-England striker Ian Wright added: "It was very emotional for Raul Jimenez. If it was me, I would probably feel the same.

"The thing about it is when he scores the goal as he runs off, you can see the realisation and that is where the emotion comes."

BBC 5 Live Breakfast

Mexican Football expert, Jamie Landeros speaking to 5 Live: "I was waiting for South Africa to show up, unfortunately it was just a one sided affair, we let them off the hook, for us Mexicans, I felt like we should have won by four or five goals and there was a lot of nerves, a lot of nerves, we saw it early. I think even our goalkeeper Raul Rangel was a little bit shaky at times, but we settled into the match and Quinones just tore the roof off over in Azteca.

"Raul Jimenez, this is his fourth World Cup, had zero goals going into this and how can you not be romantic about football? You have an incredible moment at home, in front of the fans. He had a few chances before in the match, but what a great moment for Raul and what it means for him and obviously losing his father earlier this year, just a beautiful storyline and excited for him."

Image source, Getty Images

It was a moment Raul Jimenez had waited his whole life for - and one that seemed impossible a few years ago.

The Mexico striker could have died on the football pitch in November 2020 when a sickening head injury left him with a fractured skull.

Now, less than six years later, the 35-year-old was overcome with emotion when he powered in a header to give Mexico a 2-0 victory over South Africa at the famous Azteca Stadium in the first match of the 2026 World Cup.

Jimenez, who had connected with Roberto Alvarado's right-wing cross to score his country's second goal, leapt high, celebrated wildly and then pointed to the sky - seemingly in tribute to his father Raul Jimenez Vega, who died in March.

As the majority of the 80,000 fans went wild, Mexico's players mobbed the Wolves striker, the achievement sunk in for Jimenez, who was then in tears.

"We really congratulated him because he gives a lot to the team," said Julian Quinones, who scored in the ninth minute for the opening goal of the competition to put Mexico ahead.

"Being part of a team is our pride and it's wonderful he continues to add goals to his career as a player in our national team."

Away from the red card controversy, there were some more heartwarming storylines on the opening day of this World Cup.

For pure footballing theatre, South Korea's comeback win against Czech Republic was a great way to get the ball rolling.

While the emotional scenes inside he Azteca were exemplified by Raul Jimenez's tearful response to scoring Mexico's second goal of their 2-0 win over South Africa...

This is a heads up that we will soon be joined by BBC Sport's football tactics correspondent Umir Irfan.

Do you remember Umir? He was the journalist that Pep Guardiola jokingly invited to be his assistant coach when Umir hit the then Manchester City manager with an astute question at a news conference.

Fortunately, the "brilliant" Umir is still with us at BBC Sport and will be here shortly to answer any questions you have around the tactics of this World Cup.

It might be around how he expects Scotland to set up for their opener against Haiti, or a request for Umir's view on which of Thomas Tuchel's left wingers will give England the most attacking thrust - whatever is on your mind, send us a question to get some insight from our in-house tactical maestro.

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Take a look at Umir's World Cup preview , externalepisode of Gamechangers on YouTube, where he talks to former Everton midfielder Leon Osman about Tuchel tactics and what Nico O'Reilly will bring to the side.

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One factor that is important to flag at this point is that the players receiving a red card in the 2026 World Cup will receive a one-match suspension.

This applies to both straight red cards and red cards that are the result of the same player being cautioned twice.

Fifa does hold the right to impose "further sanctions" if it deems it necessary.

It means that South Africa's Sphephelo Sithole and Themba Zwane will miss their side's match against the Czech Republic, while Mexico defender Cesar Montes will miss their meeting with South Korea.

Players can also receive suspensions for an accumulation across multiple matches.

Should players receive two bookings, they will be handed a one-match suspension.

However, yellow cards are wiped following the conclusion of the group stage, and they are wiped again following the conclusion of the quarter-finals.

You have had a chance to have your say on the red cards, this seems like a good time to bring in BBC Sport's football issues correspondent Dale Johnson for his reading of his dismissal.

• First red card: South Africa's Yaya Sithole sent off for fouling Brian Gutierrez.

Dale's verdict: The Mexico attacking midfielder was through on goal. Sithole may not have meant to bring him down, but he did. There was no doubt the South African had denied his opponent a clear goalscoring opportunity.

Image source, Getty Images

• Second red card: South Africa's Themba Zwane sent off for violent conduct after VAR review.

Dale's verdict: Zwane tussled with Roberto Alvarado, with the Mexican going to ground holding his head. It looked like a coming together off the ball, but the referee was sent to the pitchside screen by the VAR. As Wilton Sampaio was shown the replays at the monitor it was difficult to make out what had happened.

Zwane appeared to connect with an open hand to the side of Alvarado's head, not with a closed hand. Was there really a hand to the head? And if so, was it accidental or did he swing the arm?

When assessing violent conduct, the VARs are told to look for a clenched fist as a sign of aggression. This does not have to be present, but it is an indicator.

It looks exceptionally harsh, and not the kind of clear and obvious decision VAR was introduced for.

Image source, Getty Images

• Third red card: Mexico's Cesar Montes sent of for denying his opponent a clear goalscoring opportunity.

Dale's verdict: It seemed controversial initially.

Khuliso Mudau broke towards the area and looked to skip past Montes, but the South African was stopped in his tracks by a rash tackle.

Mudau was in a slightly wide position so a yellow card seemed the most likely outcome. Sampaio produced the red. Surely the VAR would step in again?

On second viewing it seemed very likely that Mudau's next touch would be to control the ball inside the area. There was no covering defender close.

Mudau would probably have had one touch, and then a shot. The VAR was not likely to get involved and tell the referee he had made a clear and obvious error.

Image source, Getty Images

In the heat of the moment, BBC Radio 5 Live commentator John Murray was also very surprised Cesar Montes was shown a red card for that challenge.

But the ratio of thumbs in our poll for each red card show there is a difference in opinion.

The consensus seems to suggest that:

• The first dismissal, for South Africa's Yaya Sithole, was a clear red card
• The second red card, for Themba Zwane, was very harsh
• And the third, for Mexico's Cesar Montes, was closer to 50-50, with readers slightly in favour of the referee's decision.

Chris Sutton
Former England forward on BBC Radio 5 Live at the Azteca Stadium

Image source, Getty Images

I suppose the one sore note for Mexico would have been the sending off of Cesar Montes at the end, who was outstanding all afternoon.

He is really important for Mexico because he's so good in the air as well and set plays are a big part of the game now.

I didn't think it was a denial of an obvious goalscoring opportunity.

The game was already in stoppage time when Mexico saw red, leaving 19 players to battle out the remaining minutes.

Khuliso Mudau made a late charge down South Africa's right channel and was brought down by a wild lunge from Mexico's Cesar Montes.

The key question was whether the centre-back had denied a goalscoring opportunity. Referee Wilton Sampaio decided he had.

• Was a red card the right decision? Thumbs up for yes, thumbs down for no.

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Mexico had already doubled their lead by the time South Africa were reduced to nine men when substitute Themba Zwane was sent off six minutes from time.

The midfielder caught the face of Roberto Alvarado as the pair were tussling for the ball.

After an intervention by the VAR, Zwane was given his marching orders.

• What do you think? Thumbs up for red card, thumbs down for too harsh.

Image source, Getty Images

Mexico led 1-0 following a dominant first-half performance at Estadio Azteca.

South Africa's hopes of turning the game around in the second half took a hit in the 49th minute when Yaya Sithole was sent off after Mexico attacker Brian Gutierrez managed to get his body in front of him and the pair tangled as he ran through on goal.

Referee Wilton Sampaio deemed that Sithole had brought Gutierrez down and denied him a goalscoring opportunity.

The red card meant South Africa had 41 minutes to salvage a result with 10 men.

• Was the referee right to send Sithole off? Thumbs up for yes, thumbs down for no.

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Again, if you missed this in real time, click on the play icon below to watch the three red cards from Mexico's 2-0 win over South Africa.

Then we will be asking you for a show of thumbs on each dismissal - thumbs up if you think it was a red card, thumbs down if you don't...

Image source, Getty Images

Before we return to the red card debate, here's a few key lines from across the World Cup that you might have missed overnight:

• Jude Bellingham has said that the squad didn't feel "connected" at the Euros - and emphasised the importance of the players "feeling loved" at this World Cup
• Canadian football journalist Har Johal has described the co-hosts' side, who are preparing to face Bosnia Herzegovina in their opening game tonight, as "the best Canadian team we have ever had"
• Our BBC Sport journalists over in the States report back on the city consumed by the NBA Finals and locals who have been priced out of going to the games
• Bosnia and Herzegovina's Edin Dzeko, 40, has said that the tournament will change the lives of young players whose country has been shaped by "the long shadow of war"