Adrian Newey says it would have been "fantastic" to work together in Formula 1 with Fernando Alonso.
The timing of the Red Bull designer's comments is fascinating, amid rumours Spaniard Alonso's management has been in touch with all three top teams about 2020.
Newey, who is Red Bull's high profile technical boss and one of the sport's most famous designers, told the Spanish magazine Esquire that Alonso is "one of the greats of the modern era".
Newey said of Alonso, who entered a sabbatical at the end of last year: "He seems to have had bad luck with some choices he has made, but whenever we have spoken with him, he has been very kind.
"Fernando's ability often exceeds the car in his hands. I think that's the mark of a truly great driver -- the ability to stand out despite not having a great car," he added.
Newey said Alonso and Vettel at Red Bull would have been "like Ayrton and Alain".
"It is one of those things that unfortunately never happened, but it was very close to happening," he revealed.
"I think we would have had a lot of success all together, but it didn't work out," said the Briton. "Red Bull has generally always tried to follow the policy of developing its own drivers. That was a small consideration.
"We met a couple of times and there were negotiations in Austria," Newey revealed. "It was close, but in the end it didn't happen."