'I think there’s another level for me to get to'

Maro Itoje has emerged from a difficult period of his career confident that he can reach new levels of performance as England progress deeper into the World Cup.

Itoje revealed during this year’s Six Nations that he had been suffering from an underlying health issue – the details of which are undisclosed – that had impacted his conditioning.

It explained the below-par displays being delivered by one of England’s world-class operators as, although he held his own on the field, he was not the dominant force that had taken the game by storm.

But having benefited from the fitness work completed during squad’s World Cup training camp, there was evidence in his starts against Argentina and Japan that the 28-year-old second row is on the rise once more.

“I don’t think one is ever fully happy, no-one is ever fully content with anything, but it’s definitely better being able to express myself physically,” Itoje said.

“During that period where it was a little bit more difficult to do that, it was a little bit more challenging.

“I had issues going on in the background which affected my ability to exercise and perform.

“And once we were able to get all those things aligned, I was able to naturally have a response from the training that I was doing.

“Having a beneficial response from the rigorous activity has allowed me to perform and play better.

“There’s no top player across any sport – whether that’s rugby, football, basketball, whatever – who has a plain sailing career, or a career that goes exactly how they wanted it.

“You can speak of any of the greats and they will probably say ‘I wish I didn’t do that’, or ‘I wish I’d done that differently’.

“I guess that whole period for me was my version of that, where I had something structurally wrong and I didn’t know it was structurally wrong until I was quite deep into it.

“To be able to persevere through that period and finally get a fix for that was great. But I personally still feel there’s a lot more to go and a lot more that I can contribute in a positive manner for this team and in this tournament.”

England have reached the quarter-finals as Pool D winners with a match to spare after Japan toppled Samoa on Thursday night.

It continues encouraging progress through the World Cup that began with victory over Argentina despite all but three minutes of the match being played with 14 men because of Tom Curry’s red card.

Itoje excelled amid England’s act of defiance against their closest group rivals, who were routed 27-10 in Marseille, but the two-time Lions tourist insists there is more to come.

“It’s funny because people after the game thought I’d played well. I thought I played alright, I don’t think I played as well as what people were telling me,” he said.

“And that’s probably because I know where I can be if I’m properly firing on all cylinders.

“The games have been a step in the right direction for me but I’m not satisfied with that, I think there’s another level for me to get to.

“So hopefully Samoa and by God’s grace the rest of the tournament will be an opportunity for me to express that.”