George Russell and Lando Norris, as the two British rookies making their debuts with Williams and McLaren respectively, are frequently associated with one another.

But actually, until fighting over the destiny of last year's FIA F2 championship, their careers have not really overlapped, with Norris (currently 19) usually a year or so behind Russell (now 21) in the junior categories. But in a way that just makes monitoring their progress all the more intriguing - as they each have CVs absolutely littered with championship titles. Just not usually against each other - until last year when Russell (driving for ART) prevailed as F2 champion over Norris (who drove for Carlin).

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Each began their karting careers in 2006, but not in parallel series. Russell was British cadet champion by 2009, following that up with another British title in 2010 in the Mini Max category. For 2011 he spread his karting wings into Europe, winning the CIA FIA KF3 championship (beating Max Verstappen and Esteban Ocon), a feat he repeated in 2012.

Russell was succeeded as the KF3 champion in 2013 by Norris. They each also competed in the FIA KF1 category, where Norris emerged as the champion. Russell was by now finding that a sudden growth spell had begun to blunt his competitiveness in karts, not something the younger (and diminutive) Norris needed to worry about.

For 2014 Russell left karts behind to make his way in car racing, winning the British Formula 4 title. Norris too dabbled in car racing (finishing third in the British Ginetta series) but also won the CIA FIA World Karting Championship, at 14 years old the youngest driver ever to do so (beating the previous record of Lewis Hamilton).

As Russell graduated to Formula 3 in 2015 - he won his second race, beating Charles Leclerc and Antonio Giovinazzi but finished only sixth in the championship - Norris emerged as champion in the lower Formula NSA British series.

Russell stayed with F3 to take third in the 2016 European standings as Norris won the Formula Renault Eurocup title. Russell stepped up to GP3 in 2017, by which time he was a Mercedes-contracted reserve driver, and won the championship after a superb campaign. Norris was equally impressive that year as he sealed the Euro F3 championship in his first full season in the category. He too had been picked up as an F1 reserve driver in this year - by McLaren.

Russell tested for Mercedes at the Hungaroring in 2017 before going on to conduct two blemish-free Friday FP1 sessions with Force India in Brazil and Abu Dhabi that year. Last year he set the unofficial lap record at the Hungaroring in the Mercedes W09. He says that spending grand prix weekends inside the Mercedes team for the last two seasons, watching at close quarters the way Lewis Hamilton operates, has given him invaluable insight.

Williams selected him late last year to be one of its full-time 2019 race drivers after he made a convincing Powerpoint presentation to senior management - and after showing a great turn of speed in the team's simulator. In the car, his style is bold and clean, with geometrically perfect lines, high entry speeds and an ability to live with quite a lot of rear end instability. Many of his F2 races revealed a thinking driver in the way he used his tyres and the timing of his attacks.

0:40 Have you spotted George and Lando playing their part in our season preview promo video? Have you spotted George and Lando playing their part in our season preview promo video?

Norris, after winning the opening round of last year's F2 championship, didn't quite gather the momentum to stop Russell, though remained in championship contention up to the final round. Meantime, McLaren had put him out in selected FP1 sessions, beginning at Spa. He was instantly at home in F1, with an aggressive style and a way of pivoting the car early in the corner that had older observers making comparisons with Nigel Mansell.

He proved a closer match to Fernando Alonso than did the incumbent Stoffel Vandoorne, and this sealed the deal for his recruitment to the 2019 race seat.

How they fare this year will be dominated by how competitive their cars are and in this regard Russell looks set to have much more of a struggle on his hands than Norris.

But 2019 can be looked upon by both as a foundation season for what will hopefully be long-term F1 careers, looking forward to the day when they can get their rivalry properly underway - wheel-to-wheel towards the front of the F1 field rather than one-step removed.

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