A look at Formula 1's completed class of 2021

Lewis Hamilton and Mercedes have finally added the last piece to the puzzle representing Formula 1's class of 2021. So let's have a look at the completed grid and the raft of driver changes for this season.

Remarkably, only three teams - Mercedes, Williams and Alfa Romeo - will head into the 2021 season with an unchanged driver line-up, while every other outfit has seen a switch, with two teams - Racing Point and Renault - also undergoing a name change.

Overall, this year's field includes four world champions, three absolute beginners and a few driver pairings that promise exciting times for F1 fans.

At Mercedes, Hamilton will be chasing a historic eighth title, a milestone that would put him in a league of his own in the sport's history books. But can Valtteri Bottas finally sustain his typically strong opening salvo and give the Brito a run for his money for the duration of the 2021 campaign?

The Brackley squad's main opposition will once come from Red Bull Racing. While the Milton Keynes-based outfit remains centered around Max Verstappen, Sergio Perez has no intention of playing second fiddle. The Mexican will be on a mission at the outset this season to prove his worth relative to the blindingly fast Verstappen.

At McLaren, Daniel Ricciardo replaces Carlos Sainz as Lando Norris' sidekick, but the Aussie has already warned that there will be no "comedy show" at Woking despite both drivers' facetious personalities. The Aussie means business and will represent an interesting benchmark for his young teammate.

Speaking of benchmarks, Lance Stroll will measure up against four-time world champion Sebastian Vettel at the re-branded Aston Martin F1 team. With each passing season, the Canadian appears to refine his talent and trend higher. How he will perform relative to Vettel - a man in search of a turnaround - is another one of F1's exciting prospects.

But perhaps the most anticipated juxtaposition of talent is the association between Charles Leclerc and Carlos Sainz. The Spaniard has fulfilled a dream by passing through the golden gates of Maranello. But be careful what you wish for as Leclerc is now firmly entrenched at Ferrari.

Two-time world champion Fernando Alonso is back on the grid this season with Alpine, the 39-year-old giving it another go with a team that, on paper, won't be fighting for race wins this year. But that doesn't mean that Alonso or Esteban Ocon won't be able to pull off a stunner if circumstances permit.

AlphaTauri's Pierre Gasly was admittedly disappointed to have not been given a second shot at Red Bull following Alex Albon's demise. But the Frenchman is determined to uphold his 2020 momentum, a task he'll undertake while also fending off his new rookie teammate, the mercurial and highly rated Yuki Tsunoda.

• Read also: Wolff explains rationale behind one-year Hamilton deal

Alfa Romeo is relying once again on F1's senior citizen, the very mature Kimi Raikkonen to lift its performance. But the step forward enjoyed last season by teammate Antonio Giovinazzi put the Italian on a par with the Iceman.

Williams' line-up also remains unchanged, with George Russell flanked by Nicholas Latifi. The Briton says he's keeping Mercedes out of his mind, but with the thought of biding his time this season before moving to Brackley in 2022 will have only been reinforced by the one-year term of Hamilton's contract.

Haas has parted ways with Kevin Magnussen and Romain Grosjean after the pair's four years of faithful service with the team. The US outfit has now gone in the opposite direction, swapping 300 Grands Prix's worth of experience for a pair of rookies. Mick Schumacher steps up to the big time with the Ferrari-powered outfit, while Russia's Nikita Mazepin will be on his best behaviour to prove that he deserves a spot among motorsport's elite.

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