Alex Fontana will make his GP3 debut at Spa this weekend after signing a last-minute deal to race for Jenzer Motorsport.
The Swiss teenager currently leads the European F3 Open standings and was a winner earlier in the year at Spa in that championship. His Jenzer move comes at the expense of Vittorio Ghirelli, who has stood down from driving duties with the team.
"This is one of the possibilities which open up in the career of a racing driver, and which you really can't say no to," Fontana said. "I'd like to thank the team, Jenzer Motorsport, for having contacted me and to thank my current [F3] team Corbetta Competizioni, who released me to drive on this occasion.
"To compete in the Formula 1 environment is a dream come true. I have never seen the GP3 car and don't know it, so I don't know what will be possible, because I'll only have the one free practice session. I will try not to worry too much and to take in the experience, and to do everything step by step."
Fontana will team with Jenzer's regular drivers Nico Muller and Maxim Zimin.