England manager Gareth Southgate applauds fans after the World Cup Group B match between England and Iran at the Khalifa International Stadium, Doha, Qatar, Nov 21, 2022. (CARL RECINE / REUTERS)

DOHA - England coach Gareth Southgate praised his players for their attacking verve in a 6-2 thrashing of Iranon Monday as they launched their World Cup campaign but warned they had to improve defensively against the United States on Friday.

"We're really pleased to start the tournament in this way and really pleased with our attacking play. We know that Iran usually are very difficult to score goals against," Southgate told a news conference.

I didn't like the end of the game. To concede two goals the way we did isn't the level that we need. So we're going to have to be better than we were today in certain aspects of our game against the USA because they're going to be coming for us full throttle, and we're going to have reset.

Gareth Southgate, England coach 

Bukayo Saka's double and first-half goals by Jude Bellingham and Raheem Sterling plus late efforts from substitutes Marcus Rashford and Jack Grealish resulted in a resounding win over Iran who had conceded only eight times in qualifying for Qatar.

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Iran's two goals - both scored by Mehdi Taremi, including a penalty - came in the last half an hour and never looked like changing the tide of the match but Southgate said he was frustrated by his side's failure to keep a clean sheet.

"I didn't like the end of the game. To concede two goals the way we did isn't the level that we need. So we're going to have to be better than we were today in certain aspects of our game against the USA because they're going to be coming for us full throttle, and we're going to have reset," he said.

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While he acknowledged the difficulties for his players to keep their focus in a game that had a total of 26 minutes of stoppage time, Southgate said England would struggle to advance in the tournament if they allowed matches to drift again.

"It's a great start for us, it's a good platform to build on but ... there are things that we need to be better at if we are going to progress into the later stages," he said.

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Southgate said defender Harry Maguire came off after feeling ill during the match but there were no other injury concerns.