Carlos Sainz declared his drive to fourth at the Singapore Grand Prix as his best to date in Formula 1, as he achieved his highest finish to date amid the chaos on Sunday at Marina Bay.

The Spaniard benefitted by being one of the drivers brave enough to choose intermediates after a downpour just before the start led to the first wet race in the 10-year history of the night race in the city-state.

The Toro Rosso driver would make some progress as conditions improved and jumped ahead to be the lead midfield runner once those on full wets pitted for the same green-striped tyres. Once in fourth, an issue took away his main challenger in Nico Hulkenberg and it became about holding off Sergio Perez to the chequered flag, which he would do.

"The best one, no doubt," he said of his race on Sunday. "Apart from the start and with all the complications this race had, I had very good pace on the wet, very good pace on the used inter against the new inter and then managing to fend off guys.

"So I would say it's one of the best stints I've done in F1."

The result also came on a big weekend for the 22-year-old after it was confirmed he will be loaned to Renault for 2018, with Red Bull keen to keep him on their books for a potential seat at the senior team in 2019.

Talk continues that Sainz may make that switch as soon as the next Grand Prix in Malaysia, but for now, he enjoyed his great result, scoring the Italian team's best result since Austin 2015.

"I'm going to look back on this one and try to create a bit of momentum," he claimed. "There's races when you're in the midfield where you do very well and you just extract a P9, a P8 out of it.

"Today, you do things very very well and you extract a P4, so that's why I was celebrating."