McLaren say they have yet to sign a contract with any driver for next season despite a widespread belief that Fernando Alonso is set for a return to Woking in a move that could end Jenson Button's Formula One career.
Red Bull announced on Saturday morning that their four times world champion Sebastian Vettel will be leaving at the end of the season with the German likely to join Alonso's current employers Ferrari.
The news set off a chain of events likely to result in Alonso's return to a team he parted with acrimoniously at the end of 2007 -- an outcome that would once have been unthinkable.
Although there has been no official word from Ferrari confirming Vettel's arrival or Alonso's departure, it has become evident that the relationship between the Spaniard and Formula One's glamour team is at an end.
The double world champion, currently in his fifth season with Ferrari, has grown increasingly frustrated with the lack of success for a team which hasn't triumphed in more than a year and faces its first winless season since 1993.
With Red Bull promoting Russian rookie Daniil Kvyat to replace Vettel in 2015, McLaren now looks to be Alonso's best bet barring even more dramatic developments.
McLaren are switching from Mercedes to Honda engines next season and the Japanese car giant is said to be particularly keen on securing a driver of Alonso's calibre.
Both the team's current drivers, 2009 world champion Button and Danish rookie Kevin Magnussen, are out of contract at the end of the season.
If it ends up that Button has to make way for Alonso, it would bring the curtain down on a 15-year career that started in 2000 and culminated in the championship with Brawn GP -- ironically after Honda pulled out.
Winner of 15 races, he moved to McLaren at the start of 2010 despite being warned by many against entering the 'Lion's Den' alongside Lewis Hamilton.
Button won eight times with McLaren but the partnership has more recently fallen on hard times.
The former champions have not won a race since Button's last in Brazil in 2012.
The 34-year-old, who expressed surprise at Vettel's move, reiterated on Saturday that he wanted to stay on and batted away rumours that he could switch to Porsche's sportscar programme.