Alex Wurz insists his outing in Saturday's Rolex 24 at Daytona International Speedway is a one-off -- and the retirement from full-time competition he announced at the end of last year still stands.

The former Toyota FIA World Endurance Championship driver was asked by Chip Ganassi to compete in the IMSA WeatherTech Sports Car Championship season opener, some 20 years after he won Le Mans at his first attempt. Wurz will be partnered by Andy Priaulx, Brendon Hartley and Lance Stroll.

Stroll serves as a Williams Formula One reserve driver, which adds an extra twist, as Wurz also works for Williams with a special focus on driver development. The Austrian will have the opportunity to guide the Grove team's new signing through the biggest weekend of his career to date.

"I consider there are four classic 24-hour races," Wurz told FOX Sports. "I've done three of them. Daytona I'd never done, and it was always on my list. It was a bit awkward that Chip Ganassi called me exactly on the day when I announced my retirement.

"But as I'm still fit and I didn't retire because I am afraid or fed up or too slow I said, 'Yeah, OK.' If he's OK with this awkward situation, I'll come and I'm very excited to do the race. It's in January, it's a relatively free month, so it's very easy to do in terms of not taking time away from Williams or Toyota."

"I would like to do the odd race in Rallycross, or maybe I'll do one more short notice appearance like Daytona," Wurz said regarding his future plans. "But I'm 100% not coming back in a full year racing seat chasing championships."

However, Wurz will be back in action next week testing the 2016 Toyota FIA WEC car.

Live coverage of the Rolex 24 from Daytona International Speedway will begin at 2 p.m. ET on FS1. Coverage will continue on the FOX family of networks throughout the event.

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