Johann Zarco will ride for LCR Honda in place of Takaaki Nakagami for the final three races of the MotoGP season, but struggling Repsol Honda star Jorge Lorenzo does not expect the move to affect his situation.
Zarco had been without a seat after his split from KTM, with the team cutting ties with the rider early after he opted to end his deal at the conclusion of the season.
The Frenchman has been granted a return to the sport with Honda, though, as Nakagami prepares to bow out for the rest of the campaign to have shoulder surgery following this week's Japanese Grand Prix.
"I'm really thankful to have this chance," Zarco said. "I will do my best to pick up some good results and to enjoy the time, because these could be the last three races I can do for a while."
Zarco has reached the podium six times in his MotoGP career, qualifying on pole four times, and a ride on a Honda bike could be seen as a threat to Lorenzo heading into 2020.
The three-time champion has endured a miserable first season with Repsol Honda, sitting 19th in the standings, and is backing Zarco to impress.
But, asked if it put him under pressure, Lorenzo said: "No, Nakagami and Cal [Crutchlow] have finished ahead of me in nearly all the races.
"[Zarco] will ride a different bike – one that, in theory, is worse – but it could be an easier bike. Surely it won't be easy for him but, because of his motivation and eagerness, he'll achieve what he can.
"Because after not having been able to ride for three or four races, he'll be very keen to demonstrate what he can do and I'm sure he'll do well."
Even if Zarco has no hopes of unseating Lorenzo or earning a permanent deal with LCR Honda, the previously mooted switch to rivals Yamaha also looks to be off the table.
Zarco had been linked with Yamaha as a test rider but told L'Equipe: "The door has clearly closed. Honda and Yamaha are two big rivals. I talked to both and made an informed choice."
Yamaha star and MotoGP great Valentino Rossi added: "It's a shame. It's no secret that Yamaha was looking at Zarco for test rider and he would have been important for us.
"Now he's close to Honda and we need to see what he decides to do for 2020, but it looks to me like we will have to find another fast test rider. It will be difficult to find someone like Johann."