Toro Rosso team principal Franz Tost says Max Verstappen and Carlos Sainz will retain their drives with the team in 2016, provided it can secure its immediate future with a new engine deal.
Though the engine plight of sister team Red Bull Racing has been well documented, Toro Rosso also remains without the critical deal it needs to compete in 2016.
Whilst it is understood to have an offer on the table to run year-old Ferrari power units, with Red Bull rumoured to be considering a reconciliation with current partners Renault, no firm contract has been signed by Toro Rosso either.
Nonetheless, Tost confirms that provided Toro Rosso does go ahead and confirm an entry for next season, it will continue with an unchanged line-up of Verstappen and Sainz.
“If the team is on the starting grid then I consider that both of them will be the drivers of Toro Rosso, because so far they have done a very good job and of course we want to keep them. I'm convinced, optimistic, that this will be the case [that we're on the grid].
Having made history earlier this year by becoming the youngest driver to start an F1 race at 17 years-old, Verstappen has proven a revelation in the STR10 by scoring in all but one race since July's Hungarian Grand Prix, including fourth place finishes in Budapest and Austin. He is also in contention to become the first Toro Rosso driver to finish the season inside the overall top ten since Sebastian Vettel in 2008.
Sainz, meanwhile, has endured a tougher rookie year, particularly in terms of reliability issues, but has cracked the top ten on seven occasions in 2015, with a best result of seventh occurring in the United States.