McLaren Autosport BRDC Award winner Dan Ticktum is to contest two rounds of the Super Formula championship in Japan with Team Mugen.
The 18-year-old winner of last November's Macau Grand Prix will fill in for fellow Red Bull junior Nirei Fukuzumi at the Sugo round on May 27, before competing at Fuji on July 8.
Fukuzumi's number-one programme is in Formula 2, and he has to miss the next three Super Formula races due to date clashes.
The first is at Autopolis on May 13, which also clashes with Ticktum's opening race weekend in the Formula 3 European Championship - his priority programme.
But the Honda-powered Mugen squad, for which Naoki Yamamoto took victory in the opening round of the 2018 series at Suzuka, has called up the Briton for Sugo and Fuji.
Ticktum said his Super Formula outings were at Red Bull motorsport advisor Helmut Marko's request.
"Helmut is putting me there to see how I cope with jumping into something new and a bit quicker," he told Autosport.
"They [the Super Formula cars] are one of the last proper racing cars there are, so I'm very much looking forward to it, and there'll be no testing - I'll be straight into free practice.
"I've tested an F2 car [in pre-season testing, as replacement for the unwell Nicholas Latifi], which is on a similar wavelength, but I know the Super Formula will be different, and I haven't even tried it on the sim."
Ticktum predicted that the old-school Sugo circuit will be something of a baptism of fire.
"I've watched a bit of onboard," he said, "and it looks interesting to say the least.
"I'll be thrown in at the deep end as usual!"
Ticktum is taking the seat occupied last year by Toro Rosso Formula 1 driver Pierre Gasly, and he said "I will send him a message at some point" for advice.
The Mugen squad has called up 18-year-old Honda protege Sena Sakaguchi, who is currently third in the Japanese F3 Championship, for Autopolis.
This round unusually has no F3 event on the undercard, leaving Sakaguchi free for the weekend.