Daniil Kvyat on Toro Rosso's shortlist for 2019

Vettel crashes into barrier during Milan F1 festival (0:34)

Sebastian Vettel crashed into a barrier while on a demo run in front of fans in Milan ahead of the Italian Grand Prix in Monza. (0:34)

MONZA, Italy -- Daniil Kvyat could make a shock return to Toro Rosso next year after Christian Horner confirmed the former Red Bull driver is under consideration for 2019.

Daniel Ricciardo's move to Renault will see current Toro Rosso driver Pierre Gasly promoted to Red Bull next year, opening up at least one space at the junior team. Red Bull has historically promoted young drivers from lower series to Toro Rosso, but none of the drivers it has under contract in formulae outside F1 have the necessary championship results to secure a superlicence.

Kvyat first drove for Toro Rosso between 2013 and 2014 and again in 2016 and 2017 after he was demoted from the senior Red Bull team to make way for Max Verstappen at the 2016 Spanish Grand Prix. After leaving Toro Rosso under a cloud at the end of last year, he signed a deal with Ferrari to become a test driver this season but Horner says it is still possible for him to make a return to the Red Bull fold with Toro Rosso in 2019.

"There are always rumours this time of year, Monza being a hotbed of that," he told Sky Sports. "I think the situation with Toro Rosso is pretty open, so I think everything is being considered. He's one of several drivers who is on the list."

Toro Rosso could have two vacant seats for 2019 as Brendon Hartely's position remains under threat following a series of disappointing results this season. Earlier this year Toro Rosso attempted to draft McLaren junior driver Lando Norris in as Hartley's replacement mid season, but the deal fell through as McLaren was not willing to sign away its option for Norris in 2019 as well.