Scott Dixon's hopes of a sixth IndyCar title have fallen flat, after a rare battery failure at the penultimate race in Portland.
The 39-year-old reigning champion had victory in sight, before his Honda-powered Chip Ganassi Racing car lost all power on lap 52 of 105.
At the time, Dixon held a seven-second lead over Australian Will Power, who would eventually cross the line first.
The Kiwi finished 16th - three laps down - and now sits 85 points behind series leader
Josef Newgarden, who recovered from a horror qualifying session on Sunday to finish fifth.
"Everything kind of went blank, you know, the screen went out," Dixon said afterwards.
"A bummer man, the car was super fast... super easy race for us. It's a shame to give away a win like that, especially in the situation that we were for the championship.
"It definitely makes it almost impossible now."
Championship contender Alex Rossi's third-place finish means Newgarden, the 2017 series champion, takes a 41-point lead into the final double-points round at Laguna Seca in two weeks.
Frenchman Simon Pagenaud is just a further point behind, but Dixon will now need a virtual miracle to claim a second straight series win.
With 106 points on offer for the winner, Dixon would need victory, a horror result from Newgarden, and midfield finishes for Rossi and Pagenaud to claim another IndyCar crown.