Briton Oliver Bearman will replace the suspended Kevin Magnussen at Haas for the Azerbaijan Grand Prix.
Magnussen has been banned from the race in Baku on 13-15 September after exceeding Formula 1’s penalty-point limit.
Bearman, who has already been signed as a Haas driver for 2025, will be taking part in his second grand prix.
The 19-year-old previously substituted for Carlos Sainz at Ferrari in Saudi Arabia earlier this season, after the Spaniard was taken to hospital with appendicitis.
He impressed by finishing seventh, after only driving the car for the first time in Saturday final practice, and the performance was key in securing him a seat on the grid next season.
Bearman has experience of the Haas car this season from free practice outings at the Emilia-Romagna, Spanish, British and Hungarian Grands Prix.
He said: “It’s definitely more of a challenge stepping in to race as a reserve driver, with limited prep time and so on, but I’m in the fortunate position of having done it earlier in the year with Scuderia Ferrari, so I can at least call on that experience.
“I’ve also had four FP1 sessions with Haas in the VF-24 already this season, so undoubtedly that will also prove to be valuable in tackling the full race weekend in Baku.”
Haas team principal Ayao Komatsu said: “This is another excellent opportunity for both Ollie and the team to work together, this time throughout an entire race weekend.”
Magnussen reached the threshold of 12 penalty points in a 12-month period after being at fault for a collision with Alpine’s Pierre Gasly during the Italian Grand Prix on Sunday.
The Dane is the first driver to be given a race ban since the penalty-points system was introduced in 2013.
Magnussen is likely to lose his place in F1 at the end of the season. The only seat available to him is the second one at Sauber alongside his current Haas team-mate Nico Hulkenberg.
Red Bull are yet to decide on the second seat at their RB team, where reserve driver Liam Lawson could replace Daniel Ricciardo. But Magnussen is not in the running there.