Tire manufacturer Pirelli fears for its future in Formula One as time runs out to agree a new contract with teams for next season.

Denny Hamlin isn't ready to say he's back, even after winning the pole for the Coca-Cola 600 with a record-setting qualifying lap Thursday night.

Closing in on Formula One leader Sebastian Vettel, Ferrari driver Fernando Alonso suggested Wednesday that Red Bull's complaints about Pirelli's fast-degrading tires are due to frustration at no longer dominating races.

McLaren's Formula One engine deal with Honda from 2015 is a vital step to ensure they can keep punching at the same weight as works team rivals Ferrari and Mercedes, managing director Jonathan Neale said on Thursday.

Honda are expected to announce shortly they will return to Formula One in 2015 as an engine supplier to British team McLaren to revive their championship-winning partnership, a company source said Wednesday.

Sergio Perez has made peace with teammate Jenson Button and their McLaren bosses after twice hitting Button during the Bahrain Grand Prix last month.

Kevin Harvick plowed through traffic to charge from seventh to first in a two-lap overtime sprint to take out Saturday's NASCAR race at Richmond International Raceway.

Spain's Marc Marquez won the Grand Prix of the Americas MotoGP on Sunday, becoming the youngest rider to win a race in the sport's elite series.

Ferrari's Fernando Alonso won a drama-packed Chinese Grand Prix in Shanghai on Sunday, well ahead of the Lotus of Kimi Raikkonen and Mercedes' Lewis Hamilton.

Sebastian Vettel and Mark Webber will be under fierce scrutiny as they return to the Red Bull team garage at this week's Chinese Grand Prix following a furious team orders row in Malaysia.