Pierre Gasly has chosen '10' as his permanent race number ahead of his Malaysian Grand Prix debut.
Toro Rosso announced earlier this week that French racer Gasly would replace Daniil Kvyat at this weekend's Malaysian GP, also staying in the car for Suzuka.
The driver swap means Toro Rosso will have the opportunity to evaluate Gasly ahead of a possible full season in 2018 as they seek a replacement for the Renault-bound Carlos Sainz.
Following Thursday's announcement, Toro Rosso confirmed that Gasly had chosen '10' as his race number. It is the same number that his car sported during his 2013 winning campaign in the Eurocup Formula Renault 2.0.
Although '10' was previously used by Kamui Kobayashi in 2014, numbers are only protected for two years.