Sebastien Buemi will drive for Red Bull for all three days of next week's Pirelli tyre test in Bahrain, AUTOSPORT can reveal.
The Italian tyre company has been given dispensation to run a three-day test with 2013 machinery, with all teams invited to attend.
Initially, six teams were announced as participating, although McLaren and Force India have subsequently confirmed they are not running.
This leaves Red Bull, Toro Rosso, Mercedes and Ferrari, whose activities will be directed by Pirelli throughout the three days.
Red Bull will have neither of its race drivers for 2014 present, meaning that Buemi, one of its two-man reserve driver line-up alongside Antonio Felix da Costa, will be given the running.
It will be the first time he has driven a latest-specification F1 car for Red Bull and his first serious running in an up-to-date car since his final season with Toro Rosso in 2011.
Ferrari has confirmed Pedro de la Rosa and Jules Bianchi will run and Mercedes is understood to be planning to field both of its race drivers, Lewis Hamilton and Nico Rosberg.