The father of England's newest Test centurion, Sam Robson, insists the Australia-born batsman was not tempted when the Baggy Green came calling last summer.

Robson was cheered on by Australian dad Jim, who is on the staff of the Sydney Cricket Ground, as he made 127 against Sri Lanka at Headingley, a knock that repaid the selectors' faith in just his third innings.

The 24-year-old hails from New South Wales but was eligible for England due to his Nottingham-born mother.

He came to England as an 18-year-old and went to to sign for Middlesex, where his good form last summer led to a behind-the-scenes tug-of-war between the rival nations.

But with his roots now firmly entrenched in London, Cricket Australia's overtures fell on deaf ears and he was put on a fast-track that led to his Test call-up this summer.

Robson senior is fully supportive of his son's decision, even though next year's Ashes series could see him pitted against some of his closest childhood friends.

"Australia wanted him last year, which probably would have been a little bit late because he was established and loves Middlesex and has a lot of friends there," said Jim Robson during day two of the second Investec Test.

"He's been here seven years and he hardly comes home anymore! My wife was born in Nottingham, so the English passport is the best thing she's ever done in her life.

"He never said 'Dad, I'm going to play for England not Australia', he's just treated every game as it comes. All he wanted to do was improve as a cricketer.

"If he ever got to the level of the Ashes it would be amazing because he's got some great mates in the Australia team - Steve Smith and Phil Hughes are two of his best mates. It would be very strange to play against them but it would be wonderful.

"I'm just a cricket lover and we just want him to do the best. Sport is global now, it doesn't matter where he is playing, he will just do the best for his team and I'm proud of him."

Robson had to settle for scores of one and 19 on his debut at Lord's last week, but his family's extended holiday allowed them to witness his moment in the sun.

"I'm glad we didn't just come for the first Test. He was so nervous for that match, I couldn't believe it. It was a bit overwhelming for him," said Jim Robson.

"It was incredible when he got his 100 here. I didn't know what to expect because you never know until you reach that magic mark. But it is very special."