The final third of the twice-round-the-clock endurance race was disrupted by rain and poor visibility, and teams complained that the conditions were untenable. Most of the final eight hours was run under a yellow flag and racing was halted under red-flag conditions for the final two hours of the event.
Teams waited at their pit stands for IMSA to make a decision. Alonso is the third Formula One champion to win the Rolex 24, joining Phil Hill in 1964 and Mario Andretti in 1972. Alonso retired from F1 in November and is racing a schedule of bucket-list events this year.
The Spaniard made his Rolex debut last year as a warmup for the 24 Hours of Le Mans. He was part of the winning team, and Alonso and Le Mans teammate Kamui Kobayashi joined the Taylor lineup to add Rolex watches to their victory memorabilia. The winning lineup also included Jordan Taylor and Renger van der Zande, the full-time drivers of the Cadillac Dpi.
Taylor also won the Rolex in 2017 when Jeff Gordon was the superstar driver in the lineup. His father, team owner Wayne Taylor, won it in 1996 and 2005.
IMSA has again stopped the Rolex 24 at Daytona because of heavy rains and dangerously poor visibility on the track.
Fernando Alonso took the lead shortly before the red flag was thrown with just over two hours remaining in the twice-round-the-clock endurance event. The Spaniard is scheduled to close the race for Wayne Taylor Racing and has driven the Cadillac to the lead in each of his stints.
Once the cars were brought to pit road, Alonso covered himself with an umbrella and leaned into the open door of the pace car to have a discussion with the driver. He's among the many drivers who have complained the track conditions are too difficult to continue the race.
The clock rolls during the stoppage.
Team Penske's quest to win the Rolex 24 at Daytona has taken a hit with under five hours remaining.
Simon Pagenaud was driving one of the Acura DPi's when the team picked up an issue with the car from its telemetry reading. Flames could be seen in the engine area as the crew inspected the car, which was ultimately taken to the garage.
Ricky Taylor was leading the race in the second Acura when he had to get out of the car because he wasn't feeling well. The race has been under caution for about an hour in heavy rain and Taylor had been following the safety car around and around Daytona International Speedway.
Taylor left pit lane on a golf cart and turned the Acura over to Helio Castroneves and the driver change dropped the team to third overall.
Roger Penske watched his cars from the pit stand as he committed to staying awake for the entire 24-hour race for the second consecutive year. Penske will be inducted into the NASCAR Hall of Fame on Friday night and turns 82 next month. He said he desired being present for the entire race so he could participate in solving any issues that plagued his two-car program.
The issue that sent the No. 6 Acura to the garage eliminated a potential showdown between former Formula One stars Juan Pablo Montoya and Fernando Alonso for the victory. Both Penske cars have consistently raced Alonso and the Wayne Taylor Racing team for the overall race lead.
Alonso did much of the heavy lifting and twice passed the Acura's to put his Cadillac out front.
The Rolex 24 at Daytona has resumed after a stoppage of more than 90 minutes for rain. Fernando Alonso is the overall race leader.
The stoppage was the first for rain since 2004 and came after a lengthy period run under caution. Drivers complained the turns at Daytona International Speedway were too slick to continue but IMSA said it was going back to green. The series then abruptly changed its mind and brought the cars to pit road to wait out the weather.
The clock continued to run on the 24-hour endurance event during the stoppage.
It was still raining when IMSA called the drivers back to their cars, but they were sent on track under yellow. Battling changing weather conditions and attrition of the performance vehicles are major elements of this event.
Alonso and Alex Zanardi, the two biggest stars in the field, both said IMSA made the right decision to stop the race.
Zanardi called the conditions the most difficult of his driving career, which compounded his project of racing without his prosthetic legs using a steering wheel to control every aspect of the car.
The double-amputee said it was "very difficult" to maintain control of his BMW at 50 mph through corners puddled with standing water.
Heavy rain drenched the field of the Rolex 24 at Daytona field with Fernando Alonso leading the endurance race at daybreak. IMSA stopped the race with a little more than seven hours remaining because of poor track conditions.
The clock continues to run during the stoppage.
The race ran for more than an hour under yellow with Alonso circling Daytona International Speedway behind the pace car. The Spaniard was critical of the track conditions and team owner Wayne Taylor called on IMSA to stop the race.
When IMSA brought the cars to pit road, the drivers were told to stay inside and wait out the stoppage.
Alex Zanardi is behind the wheel for his third stint during the rain, which has created the toughest possible conditions. Zanardi is driving without his prosthetic legs and using a steering wheel in which he controls the entire car with his hands.
Roger Penske's cars were running first and second a third of the way through the Rolex 24 at Daytona.
Penske has a pair of Acura's in the endurance race and both have run at the front of the field over the first eight hours of the event. Juan Pablo Montoya was credited with the lead at the mark.
Penske has promised to stay away for both trips around the clock as he supports his sports car program. The team owner will be inducted into the NASCAR Hall of Fame next Friday night and turns 82 next month. His stamina and commitment to his race cars awed his drivers.
The race for the overall victory shrunk seven hours into the event when the No. 77 Mazda DPi caught fire because of a fuel leak. The car had started on the pole and broke a 26-year-old Daytona International Speedway qualifying record before its race came to a sudden halt. Minutes earlier, its sister car had the same problem but Team Joest was able to repair the damage and send the car back on track.
DragonSpeed had the lead in LMP2 class eight hours into the race, while the Ferrari from Risi Competizione led the GT Le Mans class.
Riley Motorsports led the GT Daytona class in a Mercedes-AMG GT3.
The team Alex Zanardi is driving for was still climbing back from the six-lap deficit the team fell into when Zanardi's steering wheel caused an electrical problem with the BMW.
The Rolex 24 at Daytona went up in flames for Mazda Team Joest in mere minutes. Both of its cars caught fire in a 10-minute span because of fuel leaks.
Olivier Pla had taken his Mazda DPi to the garage with a fuel leak not long after the six-hour mark of the endurance race. As Team Joest was working on that car, its second entry caught fire on the track.
Timo Bernhard was driving when flames began to shoot from the back of the Mazda. That entry had broken a 26-year-old Daytona International Speedway record to qualify on the pole for the twice-round-the-clock event.
The entry had to be towed back to pit lane and both Team Joest entries dropped to the bottom of the class running order.
Bernhard said it was a fuel leak, same as the sister car.
Reliability for the Mazda's had been questioned by others in the field before the race began because the cars were so strong in testing earlier this month. Mazda continued to show steady speed in the days leading into the race, but some wondered if the cars could last the entire race.
Fernando Alonso had no intention of staying awake for the entire Rolex 24 at Daytona. He didn't even plan to really watch it, either.
Alonso put Wayne Taylor Racing into the lead in the twice-round-the-clock endurance race, then said he had a long nap in his future. He was the second driver in the Taylor lineup and passed Helio Castroneves to put the Cadillac at the front of the field.
Over nearly three hours of driving, the Spaniard built a lead of nearly 15 seconds.
Asked how his triple stint was, Alonso simply stated: "It was OK."
He said he would shower, eat dinner and then sleep but wouldn't turn the race on television because it would interfere as he attempts to conserve energy.
Alonso is in the Rolex for the second consecutive season and this race is kicking off his post-Formula One career. The two-time F1 champion retired in November and is racing only in events that bring him joy.
He will return to the Indianapolis 500 in May.
The steering wheel designed by BMW for Alex Zanardi to drive without his prosthetic legs has created problems for the Bobby Rahal-owned team.
Zanardi had a difficult time getting the wheel locked into place when he began his stint in the Rolex 24 at Daytona and the backup steering wheel also had difficulties. Zanardi said after his stint it was a connection issue that has stymied BMW after a year of working on this project.
When Zanardi turned the car over to teammate Jesse Krohn the BMW stalled exiting pit road and IMSA threw a caution. Krohn had to take the car to the garage for repairs, which Zanardi watched from a closed-circuit television. The car got back on track but Zanardi was unsure if he will be able to drive again in the race if the steering wheel is not working.
The wheel controls the accelerator, brakes, throttle and everything Zanardi needs to compete.
The defending champion team in the Rolex 24 at Daytona has gone to the garage with damage to its Cadillac.
Action Express Racing won the endurance race last year and was trying to win a second title at Daytona International Speedway in the final race of Christian Fittipaldi's career. The Brazilian is a three-time Rolex winner and picked this event to conclude his time as a driver.
Fittipaldi was driving when he spun off course in the horseshoe. He brought the car to pit road and it was then pushed to the garage.
The team is already down a driver because Mike Conway had travel issues that kept him in England and forced Action Express to go with only three drivers. The lineup of Fittipaldi, Joao Barbosa and Filipe Albuquerque won the race last year.
The Chip Ganassi Racing entry that won the GT Le Mans class last season also had an early issue when Ryan Briscoe went off course on cold tires. The Ford GT had to go to the garage to replace the nose, wing and right rear toe link. The car went down three laps.
Corvette Racing also had an early setback when its two cars ran into each other on pit road.
Alex Zanardi's first stint in the Rolex 24 at Daytona had a brief hiccup when his steering wheel didn't lock into place when he got into the BMW.
Zanardi is racing for the first time without his prosthetics and for the first time in North America since the 2001 crash that severed both his legs. BMW designed a steering wheel that allows him to do everything with his hands, and the wheel is specific for the Italian.
When he climbed in for the driver change roughly 90 minutes into the race, the wheel didn't snap into place and Zanardi frantically waved for assistance. A crew member leaned into the cockpit, removed the wheel and placed a second one in the car.
The second wheel also needed a strong push to get into place and Zanardi was finally able to race. BMW has him second in its rotation of four drivers.
The Rolex 24 at Daytona has started with a heavyweight lineup that includes beloved champion Alex Zanardi in a field full of superstars.
The two-time CART champion and former Formula One driver is racing in North America for the first time since both legs were severed in a 2001 crash in Germany. BMW designed a steering wheel that allows Zanardi to race without his prosthetics using levers to brake, accelerate, shift and adjust the fuel parameters in the engine.
The Bobby Rahal-owned team didn't reveal its driver rotation before the start of Saturday's race but Zanardi was expected to get in the car at the first driver change. The team has choreographed the stops to roughly 15 seconds and that includes swapping the steering wheel for his teammates.
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