Spain's Alex Palou clinched his fourth consecutive IndyCar Series title – and fifth in six seasons – on Sunday to cement his status as one of the greatest drivers in the history of the American competition.
Palou finished 10th in the day's second race at Milwaukee — won by Mexican driver Pato O'Ward - to take an an insurmountable lead in the overall standings with one race remaining.
"So incredible, man," the 29-year-old Chip Ganassi Racing driver said moments after becoming only the second man in history to win four straight IndyCar titles.
"Just so proud of this team. Today was a really bad race for us, like we were suffering all the time, and I was just like 'Keep focused, keep on going,'" Palou said.
"It's great to have another championship, and yeah – ready for the next one."
Palou had been all but assured of wrapping up the title on Sunday after a chaotic weekend of racing forced drivers to race twice in the same day.
Heavy rain on Saturday had forced race one of the weekend to be halted after 90 laps with the completion delayed to later on Sunday.
Earlier in the day, in race two of the double-header, Palou had started on pole and led at different stages of the race before finally having to settle for a fifth-place finish.
That result wasn't enough to formally clinch the title but Palou extended his championship lead over Kyle Kirkwood to 97 points.
That meant Palou effectively only had to finish the rearranged conclusion to race one to be certain of taking an insurmountable lead over Andretti Global driver Kirkwood to claim the crown.
In the event, Palou came home safely in 10th place with Kirkwood five places behind.
Palou is the second driver to win four championships in a row after Sebastien Bourdais, who completed his quartet of wins between 2004 and 2007.
He is only the third driver to win five titles and is now firmly in the hunt to reel in Scott Dixon (six) and A.J. Foyt (seven) as he prepares to head into next week's season finale at Laguna Seca in California.
Asked how many more titles he felt he could win, Palou said: "I don't know, man, I guess we'll find out. But I'm very excited for next weekend – it's my favourite racetrack of the year."