Mercedes confirmed the worst-kept secret in Formula One this week as they announced George Russell will drive for the Silver Arrows.

Russell will take the seat of Valtteri Bottas, who is set to join Alfa Romeo after failing to mount a drivers' championship challenge during his time with Mercedes.

A product of the Mercedes junior driver programme, Russell earned his spot with Mercedes through a series of impressive performances for Williams, while he was also praised for his display filling in for future team-mate Lewis Hamilton at the Sakhir Grand Prix last year.

But how do Russell and his predecessor compare? Stats Perform looks at the numbers from their respective careers to assess whether Russell can be an upgrade.

Bottas too often the bridesmaid

Bottas has sprayed the post-race champagne plenty of times already this season. He has claimed seven podiums in 2021 but has not been on the top step. Indeed, with six third-place finishes and one second-place, Bottas has collected the most podiums without winning in the campaign so far.

That is reflective of Bottas' career with Mercedes. Unlike the man he succeeded, Nico Rosberg, Bottas has never truly been a threat to Hamilton despite the dominance the team has enjoyed.

The Finn has finished second 29 times in his career, more than any other driver who has failed to win the championship. Only Rubens Barrichello can match him. Since 2017 when he joined Mercedes from Williams, Bottas' total of 45 second and third-places finishes is more than any other driver.

And when he reflects on his Mercedes tenure, Bottas will in part have to look back on a number of missed opportunities. Rene Arnoux (11.1%, 2 of 18) and Nelson Piquet (20.8%, 5 of 24) are the only drivers to in F1 history to claim a lower percentage of victories from pole position than Bottas (29.4%), who has qualified fastest 17 times but gone on to win the race on just five occasions.

George growing in stature

While it can be argued Bottas has struggled to get the best out of what has been, for the most part, the clear top car on the grid, Russell has this year taken a Williams car that pales in comparison to what the team produced during their glory years beyond expectations.

Though his second-place at the Belgium Grand Prix was secured in part because the weather meant only two laps could be completed behind the safety car, his reward for a brilliant qualifying performance made him the first Williams driver to claim second since Lance Stroll in 2017.

Russell has elevated Williams from backmarkers to regular residents in the midfield, reaching Q2 of qualifying in 12 of 13 attempts in 2021. He had reached that stage nine times in his previous 37 qualifying appearances.

Even when the Williams car was the worst in the field in 2019, Russell still had the edge over Robert Kubica in qualifying. He qualified ahead of his team-mate in all 21 grands prix, becoming the first rookie driver to achieve that feat.

Bottas had the edge at the Sakhir Grand Prix when Hamilton was absent, beating Russell to pole, but the Brit was only denied victory as a puncture handed the win to Sergio Perez.

If he can avoid such misfortune going forward, Russell's track record with Williams this year indicates he could provide Hamilton with stiff competition in qualifying and on raceday.