Why the time is right for Valtteri Bottas to make way for George Russell

One of F1's worst kept secrets is finally out. Valtteri Bottas will leave Mercedes to race for Alfa Romeo in 2022, paving the way for George Russell to join the world champions and partner Lewis Hamilton next year.

Mercedes has yet to announce Russell -- presumably so as not to overshadow Bottas' news -- but this one has been a long time in the making. Ever since Russell took F1's feeder series -- GP3 and Formula 2 -- by storm, his card was marked for a rise to the top, and as Mercedes junior driver he had a clear route to very front of the grid.

For the past three years, Russell has served an apprenticeship at the Mercedes-powered Williams team at the back of the grid. During that time, it has become increasingly clear that he is ready to race with a top team, and with Bottas' results and age counting against him, it became a matter of when, not if, Mercedes made the switch.

Russell's performance as a substitute for Hamilton at the Sakhir Grand Prix last year, in which he would have taken victory had it not been for a mix up of tyres in a pit stop and a puncture thereafter, made it clear he was ready. Further proof of his talent came during a remarkable run of qualifying sessions for Williams this year, with three Q3 appearances and just one Q1 knockout from 13 qualifyings, with the clear highlight being his remarkable second place grid position (and therefore second place finish) at the rain-affected Belgian Grand Prix.

Bottas, meanwhile, has been a valuable member of the Mercedes team for the past five years but, crucially, not an irreplaceable member. He got his big break with Mercedes when Nico Rosberg unexpectedly bowed out after winning the 2016 world championship, leaving team principal Toto Wolff in the lurch. Wolff had been an early investor in Bottas' career and drafted the Finn in to partner Hamilton, giving him the opportunity all drivers in Formula One want: a shot in the best car on the grid.

Bottas did all he could to seize the opportunity, but it pitched him against the greatest driver of a generation in Hamilton. In four and half seasons he has undoubtedly contributed to Mercedes' dominance of Formula One, but has always played second fiddle to Hamilton.

Since joining at the start of 2017, he has signed rolling one-year deals, which have left him facing questions about his future each summer. Had he been given a contract longer than a single year, there's an argument that he may have built a more solid platform for title success, but in F1 results are currency and Bottas wasn't able to secure them consistently enough to earn a multi-year deal.

Nine wins from 92 starts at Mercedes isn't awful, but it pales in comparison with Hamilton's 46 in the same period. There's no doubt that on his day Bottas can set a quicker qualifying time than Hamilton or even beat him to a race victory in a straight fight, but there is very little evidence that he can do it consistently enough to mount a title challenge.

The first half of the 2021 season backs that theory up. As Hamilton has raised his game to meet the challenge from Max Verstappen in this year's title fight, Bottas has slipped further back. It's not a bad situation for Mercedes as Bottas is still in the mix enough to play a beneficial role in race strategy from time to time, but over the 13 races so far, he has already dropped nearly 100 points to Hamilton. He has outscored his opposite number at Red Bull, Sergio Perez, but only just.

But that doesn't mean Mercedes' decision to replace Bottas was straightforward. By sticking with Bottas in 2022, Mercedes would have retained the inner harmony that has become a defining factor in one of the most successful F1 teams of all time. Russell's talent threatens to disrupt that harmony as he comes to the team with the skills and ambition to pose an internal threat to Hamilton in what could be the final two years of the seven-time champion's career.

Upsetting your existing star driver is a risk, but ultimately the decision rested on what was best for the long-term future of the team, not Lewis Hamilton.

Next year, Formula One enters a new era with a new set of technical regulations. Hamilton has committed to two more seasons with Mercedes but beyond that there is no guarantee he will stay in F1. As he said ahead of the Dutch Grand Prix last Thursday, Russell, who is 13 years his junior, is the future, and Mercedes could no longer ignore that fact. Therefore, delaying Russell's promotion for another year would have made little sense. Bottas had his chance to prove himself as a worthy successor to Hamilton, but ultimately fell short.

Meanwhile, Mercedes' main rivals for 2022, Red Bull and Ferrari, have young drivers in Max Verstappen and Charles Leclerc who already have experience racing at the front of the grid. Russell is from that same generation, and during his three years at Williams has shown a similar level of potential.

There's no doubt that he will push Hamilton harder than Bottas, which is something Mercedes will have to manage carefully, but Hamilton has always said he doesn't mind who his teammate is. That statement will no doubt be put to the test by Russell next year, but running two of the best drivers on the grid is always a nice problem to have, and with Hamilton's retirement looming either at the end of 2023 or in the year's shortly after, any short-term pain in team harmony will be worth it for the long-term gain of getting Russell up to speed.

While it may cause Mercedes some headaches, for those watching on from the outside it will be fascinating to watch. F1 is always at its best when the top teams are filled with the top drivers, and in Russell and Hamilton, Mercedes will have the perfect mix of youth and experience. Possibly the best of two generations of drivers in equal machinery at the start of a new era in the sport.

For Bottas, Alfa Romeo was the best option left on the table. Even if he fell short of challenging for the title during his time at Mercedes, the 32-year-old still deserves a place in F1 and he represents a very safe and experienced pair of hands for a team looking to move up the grid under F1's new ruleset.