Sainz 'the cork in the bottle' in F1 driver market jigsaw
A host of drivers on the grid have now been left on tenterhooks waiting on the man seven-time champion Hamilton is replacing at the Scuderia, Carlos Sainz, to announce his next move.
"Carlos is the cork in the bottle. We are all waiting for him to make a move, then all the pieces in the puzzle will fall into place," Haas driver Kevin Magnussen said on Thursday.
Sainz dashed any hopes his paddock rivals may have entertained of announcing a decision this weekend at his home Spanish Grand Prix.
"The latest news is I will take a decision very soon," he said.
"I don't want to wait any longer, it has taken up space in my head for a few month now.
"But I'm not clear in my mind, I'm not sure one way or another.
"I'm discussing it with my (management) team, I need a couple of quiet days at home.
"It's been a very hectic couple of weeks, I've not had time to take a decision yet," he added.
A straight swop with Sainz moving to Mercedes appears unlikely.
If F1's rumour mill is anything to go by Mercedes are reportedly sweet on replacing Hamilton with their F2 teenage driver Kimi Antonelli to team up with George Russell in 2025.
One possible new employer for Sainz, who won in Australia this season, is Williams, taking Logan Sargeant's seat alongside Alex Albon.
Sauber, due to become the Audi F1 factory team, are also interested in the Spaniard.
Alpine are shedding Esteban Ocon for next season, with teammate Pierre Gasly's position yet to be confirmed.
At Haas, Nico Hulkenberg is moving on to Sauber next year, leaving uncertainty over the futures of Sauber's current pairing Valtteri Bottas and Zhou Guanyu.
Magnussen's Haas contract expires at the end of this season, with Oliver Bearman set to join the Ferrari-powered team.
The Ferrari-academy youngster excelled when standing in for the appendicitis-hit Sainz in Saudi Arabia, and will be behind the wheel of Hulkenberg's Haas in opening practice in Spain on Friday.
Yuki Tsunoda has a contract extension until at least 2025 at Red Bull's junior team RB, but there is a question mark over whether Daniel Ricciardo will still be alongside him next term.
Ricciardo was in the points last time out in Montreal.
"I needed a result like that in Canada," he said.
"I'd like to stay in the Red Bull family, I really don't see myself anywhere else, but I have to earn my place," he added.
Fernando Alonso is fully committed to the Aston Martin project with the Spanish veteran signing until at least the end of 2026.
And it is hard to see team owner Lawrence Stroll sacking his son and Alonso's teammate Lance.
McLaren are sticking with their exciting duo Lando Norris and Oscar Piastri while Sergio Perez has just signed a new two-year deal to remain three time world champion Max Verstappen's teammate at Red Bull.