Nissan Formula E driver Oliver Rowland will miss this weekend's Portland E-Prix double-header due to an illness.
The announcement came on Friday morning in America ahead of track running, with the Briton's spot set to be taken by Nissan's reserve and simulator driver Caio Collet.
A statement from Nissan said: "Oliver Rowland will not compete in this weekend's Portland E-Prix double-header due to illness. The team's reserve and simulator driver, Caio Collet, will step into car #22 instead.
"The whole team wishes Oli a quick recovery and to see him back in action in London next month."
Rowland's title aspirations will all but end with his absence in America, having enjoyed a strong season after returning to Nissan for the 2023-24 campaign.
The Briton rejoined the Japanese manufacturer after parting ways with Mahindra last term and midway through a difficult season.
This year Rowland has taken six podiums across 12 races, which included a run of four rostrums in succession that launched him into the mix of the title battle.
This culminated with only his second Formula E victory in Misano, having finished second on-the-road to Antonio Felix da Costa before the Porsche driver was subsequently disqualified for a technical breach, for which the German manufacturer lost its appeal earlier this week.
Rowland was also on course to double up in the Misano sequel, but an incorrect lap counter meant he ran out of energy on the final lap while leading.
After a double podium in Berlin and two more points finishes last time out in Shanghai, Rowland sits fourth in the drivers' standings heading into this weekend's event, just 36 points behind championship leader Nick Cassidy, who could claim the title this weekend with the right results.
It means Collet will make his Formula E race debut this weekend, having previously tested with Nissan in the Misano and Berlin rookie test sessions.
The Brazilian joined the team at the start of the year and has performed his duties alongside a campaign in Indy NXT, the feeder series to IndyCar.
In the American single-seater championship, Collet sits third in the standings having taken four podiums across eight races. He also previously won races in Formula 3.
