2015 GoPro Grand Prix of Sonoma: Dixon Wins Fourth IndyCar Title on a Countback

Scott Dixon won the GoPro Grand Prix of Sonoma on 30 August 2015, the final round of the IndyCar season, after 85 laps on the road course in California. The win was his third of the year and his 38th in IndyCar, and it gave him a fourth series championship on a countback after the title race ended level with Juan Pablo Montoya.

Why did the Sonoma finale matter?

The race closed out a sixteen-round campaign, and it was the eleventh edition of the event at Sonoma. Several drivers still had a realistic chance of the championship, so every point and position at the finish carried real consequences for the title.

IndyCar had changed its points system for 2015, awarding double points at the Indianapolis 500 and the season finale. That meant that a driver could collect up to 104 points in the final race, which kept six contenders mathematically in the hunt.

Scott Dixon won the Sonoma finale and, on a countback, the 2015 IndyCar championship.

Who was in the title fight before the race?

Montoya had earned 500 points after the ABC Supply 500, and he led Graham Rahal by 34 points in the standings. Dixon was third, 47 points behind Montoya, while the defending champion Will Power sat fourth, 61 points back. Montoya's position gave him a clear path to the title if he could finish strongly.

Helio Castroneves was fifth, 77 points off the lead, and Josef Newgarden was just 87 points behind Montoya. Chevrolet led the manufacturers' championship going into the finale.

What was the background to the race weekend?

The race was the first IndyCar event since the death of Justin Wilson, who had been fatally injured in the ABC Supply 500 the weekend before. Despite the sadness across the paddock, IndyCar officials kept the schedule, including the championship celebration in San Francisco.

Andretti Autosport announced that Oriol Servia would drive the team's No. 25 Honda, which Wilson had usually driven. Mikhail Aleshin also returned to the series, driving a one-off Schmidt Peterson Motorsports Honda after a long recovery from injuries.

How did the track and field look?

Sonoma Raceway was the setting for the race, and it was the eleventh consecutive year that IndyCar had raced at the track. It was also the first time the track had hosted the championship-deciding race, and the first season finale on a road course since the 2007 Champ Car World Series.

Twenty-five cars and drivers were entered. All of them used the Dallara DW12 chassis, with manufacturer aero kits and Firestone tyres, and six drivers in the field had won at Sonoma before.

How did practice go?

The first practice session lasted 210 minutes and took place on Friday afternoon. Will Power set the fastest time with a lap of 1 minute 17.4858 seconds, ahead of Graham Rahal and Ryan Hunter-Reay. The timing sheets showed how closely the leading cars were matched going into the race.

The second practice session on Saturday morning lasted 45 minutes, and Hunter-Reay led it with a lap of 1 minute 16.8702 seconds. Rahal and Josef Newgarden were second and third, and ten drivers broke Power's track record in the session.

How did qualifying set the grid?

Qualifying took place over three rounds on Saturday afternoon. Simon Pagenaud led the first group, and Power topped the second group and the first round overall. Power's pole gave him the quickest car on the day, and the fast six were separated by very small margins.

In the final round, the Firestone Fast Six, Power set the fastest lap again and won pole for the sixth time in 2015. His lap of 1 minute 16.2597 seconds also beat his own track record from the year before. The two leaders in the standings, Montoya and Rahal, lined up fifth and sixth.

What happened before the start?

All 25 drivers took to the track for a thirty-minute warm-up on Sunday morning, and Power was again the quickest, with Takuma Sato and Pagenaud second and third. The race itself began at 2:07 p.m. PDT with a rolling start in sunny weather.

Before the start, a tribute video played for Justin Wilson, followed by a moment of silence. The Britain anthem, God Save the Queen, was also played in his honour, since he had been born there.

How did Power dominate the early laps?

Power took the race lead straight away, and the rest of the field strung out behind him. Rahal nearly spun at turn four after Marco Andretti tapped him from behind, but he saved it. He led the field with a commanding early pace.

Power led 26 of the first 34 laps. Castroneves was forced to pit early on lap three for nose damage and new tyres, and several cars towards the back, including Bourdais, Vautier, Hawksworth and Jakes, also pitted early in the hope of a caution, but the race stayed green.

How did Montoya's contact change the race?

Power was spun from behind by his teammate Montoya in turn four on lap 39, which damaged Montoya's front wing. Both drivers had to pit to repair the damage and lost many positions in the process, which swung the championship picture.

After that incident, Rahal climbed back to second in the standings, only 10 points behind Montoya. Montoya's title hopes were now in danger, and he worked his way back up the order as the cars cycled through the stops.

How did the leaders trade places in the middle?

Saavedra and Tony Kanaan of Chip Ganassi Racing traded the lead before the stops. Saavedra gave up the front to his teammate Kanaan on lap 45, who had better tyres at the time. The changes at the front kept the outcome open until the late stages.

Dixon, who was carefully saving fuel, moved forward through the field. He held on to the lead for much of the later race and used the restarts to his advantage.

How did the late stages unfold?

With fewer than thirty laps left, Dixon edged away from the field while nursing his fuel. Kanaan defended against Montoya in an attempt to stop him from gaining points on the leader. The final restarts were decisive, and every position was contested until the flag.

On lap 65 James Jakes crashed hard into the tyre barriers in turn nine, which brought out the third caution. Jakes walked away unhurt, and Dixon remained ahead on points during the yellow flag.

On the restart Hawksworth made contact with Carlos Munoz in turn seven, and the caution that followed gave the leaders a chance to bunch up again. Montoya moved closer to Dixon in points, and the gap was reduced to a handful of points.

What decided the final laps?

With nine laps to go, Sebastien Bourdais made contact with Rahal in turn seven, which sent Rahal around from sixth and ended his hopes of the title. Montoya benefited from the incident and moved up to seventh, cutting Dixon's points lead to just two.

Dixon then gained extra points for leading the most laps, and the gap went back out to four. Bourdais received a drive-through penalty for avoidable contact, and Montoya moved up to sixth, tying Dixon for the championship lead on points.

Montoya chased Ryan Briscoe over the final five laps, cutting several tenths of a second on each corner, but he finished sixth, 1.18 seconds behind the fifth-placed driver. Dixon won the race ahead of Hunter-Reay and Kimball.

Who finished where?

Dixon won from Ryan Hunter-Reay in second and Charlie Kimball in third. Kanaan and Briscoe filled out the top five, while Montoya, Power, Sato, Rodolfo Gonzalez and Aleshin finished sixth through tenth. The finishing order reflected how difficult the race was to manage for most of the field.

Dixon led the most laps and earned two bonus points for it, which helped him take the title. Helio Castroneves set the fastest lap of the race but finished 15th, while Newgarden finished 21st, one lap down.

How was the title decided?

Dixon and Montoya ended the season level on 556 points, so the title was settled by race wins. Dixon had three wins in 2015 at Long Beach, Texas and Sonoma, while Montoya won twice, at St. Petersburg and the Indianapolis 500.

With four titles, Dixon now stood level with Mario Andretti, Sebastien Bourdais and Dario Franchitti, behind only A. J. Foyt among American open-wheel champions. Montoya had also won a title on a tiebreak in 1999, which made the 2015 finish even harder to accept.

What did the drivers say afterwards?

In victory lane Dixon said the team had always believed they had a chance, a feeling that reflected a season defined by close margins, and he dedicated the win to the Wilson family. He said the race had been run with heavy hearts, and that Wilson would have wanted the drivers to race.

Montoya said the team had thrown the championship away by failing to close it out, and he blamed the double points for the outcome. Penske's Roger Penske said his team had raced well and congratulated Ganassi, while Chip Ganassi said he was shocked by the result.

What did the finale mean for the manufacturers?

Chevrolet won the manufacturers' championship with 1,645 points over the season, and Honda was second, 466 points behind. The result showed the strength of the Chevrolet programme across the year. The result showed the strength of the Chevrolet programme across the full season.

Rahal finished fourth in the points, which was his best championship position, while Power moved up to third after his recovery to seventh. Castroneves stayed fifth, and Newgarden dropped to seventh, five points behind Hunter-Reay.