Motorsport: Denny Hamlin avoids mid-race mayhem to win Daytona 500

Race leader Ryan Newman seems to have survived a spectacular crash that marred the finish of the iconic Daytona 500 Nascar race in Florida.

Denny Hamlin avoided a series of late crashes that took out half the field to win his second consecutive title at Daytona International Speedway on Tuesday (NZ time).

But his celebrations were soured by the drama still unfolding out on the track, as emergency crews rushed to Newman's aid.

The Roush Fenway Racing driver flipped within sight of the finish, spinning and skidding several metres down the track on his roof, before coming to a standstill. 

Screens were erected to obscure public view of the wreckage and Newman was eventually taken to a local hospital for "evaluation".

"He is in serious condition, but doctors have indicated his injuries are not life threatening," said his team in a statement.

Newman's accident was one of several incidents throughout the race.

With 16 of 209 laps remaining, frontrunner Brad Keselowski was shunted from behind and spun out, sparking a chain reaction that saw cars strewn across the raceway in various states of wreckage.

Keselowski never rejoined the race, while others tried to continue, but were forced out later.

Trailing three cars behind the initial impact, Hamlin miraculously emerged unscathed and avoided several subsequent skirmishes to take the 'Great American Race' in a photo-finish from Ryan Blaney.

But his post-race emotions were divided between wild celebration and concern for Newman.

"It's a weird balance of excitement and happiness for yourself, but someone's health and their family is bigger than any win in any sport," he told Fox Sport. "We are just hoping for the best."

Hamlin's team only learned of Newman's condition after they had celebrated their win with a front-straight spinout and apologised afterwards, when the circumstances became clearer.

"Some people may have saw us and said, 'well, these guys are celebrating when there's a serious issue going on'," said team owner Joe Gibbs. 

"I apologise to everybody, but we really didn't know. We got in the winner's circle and that's when people told us.

"We know what can happen... we just don't dream that it will happen."

This year's race, started by President Donald Trump, was postponed from Monday (NZ time) by heavy rain.