Already down 2-0 in just the 33rd minute, Collins was given a straight red for the challenge, which caught Grealish high on the thigh near his groin.
As the home side hoped for a VAR reprieve, it took referee Anthony Taylor no time to produce the red card.
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In commentary for talkSPORT, former Aston Villa and Chelsea midfielder Andy Townsend described the challenge as “ridiculous”.
Former Dutch international Nigel de Jong – who famously avoided a red card in the Oranje’s 2010 World Cup final loss to Spain for a similar challenge on Xabi Alonso – said Collins had been watching “too many of (his) YouTube videos”.
Wolves coach Bruno Lage said he didn’t believe Collins went into the challenge to hurt Grealish, but admitted the challenge was careless.
”I don’t believe that Collins wanted to do that. He tried to play the ball, but when you see that you need to admit that it can be yellow, it can be red,” he said.
Grealish put City in front after 55 seconds when he was in the right spot to put a cross into the back of the net, before Erling Haaland scored their second in the 16th minute.
It was Haaland’s 11th goal in seven league games since his offseason arrival from Borussia Dortmund – with the majority coming from right in front of goal.
“I didn’t know he could score from outside the box,” Grealish said jokingly, while calling Haaland “the best striker in the world playing up front.”
Wolverhampton’s already-slim chances virtually ended Collins sent off.
Phil Foden swept in a right-wing cross from Kevin De Bruyne, who provided a similar assist for Grealish’s goal, in the 69th minute to round off a win that took City above Arsenal into first place.
City has scored 23 goals in the first seven games of its title defense – comfortably more than any other team – and Haaland has almost half of them.
On the other hand, Grealish has just the one – and he knows he needs to score more to justify being the most expensive Premier League player ever after joining from Aston Villa for more than $170 million in the offseason.
“Rightly so people have been asking questions – I should be scoring more and getting more assists,” the England international said.
“I am always going to have people talking about me with the money that was spent on me, but all my career I haven’t scored enough goals. I do want to add that to my game.”
— With AP
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