Lewis Hamilton 'at the peak of his game', says Mercedes' Paddy Lowe

Mercedes chief Paddy Lowe believes Lewis Hamilton is now "better than he's ever been" as the Briton bids to close out his third world title as early as this weekend's United States GP.

Hamilton edged closer to the landmark of winning three drivers' championships with his ninth victory of his dominant season in Sochi. The 30-year-old will retain the title if he outscores Sebastian Vettel by nine points and Nico Rosberg by two in Sunday's race.

Although Hamilton moved from McLaren to Mercedes in 2013, technical chief Lowe has been alongside for all of his 42 wins having made his own transfer from Woking to Brackley six months later.

And Lowe reckons Hamilton has never been in better form than he is now.

"Lewis is a fantastic driver. I've had the privilege to work with him through all his race wins actually, right from the beginning," Mercedes' technical chief told Sky Sports News HQ.

"He was always a special driver and I think we're seeing him now actually at the peak of his game. He's better than he's ever been and that's a very difficult driver to beat."

Hamilton's previous two titles, in 2008 at McLaren and last year with Mercedes, have been secured at the final race of the season following year-long duels with Felipe Massa and team-mate Rosberg respectively.

However, Hamilton has only been beaten by Rosberg in three races so far in 2015, although the German has still scored sufficiently strongly for Mercedes to have already wrapped up their second consecutive constructors' title.

Lowe and Hamilton have worked together since Lewis's entry into F1 in 2007

Lowe believes Rosberg continues to drive well too and is pleased that the pair's competitive rivalry on the track hasn't derailed the team's title-winning objectives.

"They're both at the top of their game and that's tremendous for us. They are great assets to the team, great team players and have great respect for each other," said Lowe of the Hamilton-Rosberg partnership, which will continue into a fourth season in 2016.

"We have made progress over the last two years in terms of how the drivers work together and maintaining at the same time that sporting element between them.

"We want to put on a great spectacle because that's why we're here and I think we're managing to do that without friction between the drivers."