Lewis Williamson will contest his second Formula Renault 3.5 round of the season at Barcelona this weekend
Red Bull has nominated the Silverstone GP3 winner to substitute for ISR's regular driver Daniel Ricciardo, who is competing for HRT in the clashing Japanese Grand Prix.
Williamson, last year's McLaren AUTOSPORT BRDC Award winner, raced for ISR at Aragon's opening FR3.5 round in April, when Ricciardo was fulfilling Friday Formula 1 practice duties for Toro Rosso in China.
"[At Aragon] he made a mistake at the start, but then the pace, particularly regarding the first race, wasn't so bad at all," said ISR team boss Igor Salaquarda.
"I hope he will be better [having competed in a season of] GP3. In the end, GP3 didn't finish especially well, but it was a competitive year. Red Bull Williamson for this race, and we are talking about running him next year. But it is still very early and we have to see after the race and after testing."
A two-day FR3.5 collective test is scheduled at Barcelona on October 11-12. ISR will test Williamson's GP3 contemporary Nick Yelloly on the first day of running on Tuesday. Yelloly has extended his race-by-race deal with Pons Racing to complete the season this weekend.
Pons announced the appointment of Emilio de Villota Jr as team manager last week. De Villota Jr has experience running teams for his father, former F1 driver Emilio de Villota, in European F3, Euroseries F3000 and Superleague.
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