Red Bull: Mexican GP now only realistic chance to win again in 2018

Red Bull has won three races this year and challenged for victory last time out at the high-downforce Singapore circuit, with Max Verstappen ultimately losing out to Mercedes driver Lewis Hamilton.

Verstappen won in Mexico last year, and Horner hopes the Austrian team can mount another challenge at the Mexico City circuit.

"I think realistically Mexico is probably the only shot we've got left, under normal circumstances," Horner said.

"Hopefully we can get a few more podiums in before the end of the year."

Mercedes F1 boss Toto Wolff said that it was good to have Red Bull in the mix as the title fight intensifies, with Hamilton locked in a battle with Ferrari's Sebastian Vettel.

Verstappen's second place in Singapore allowed Hamilton to put a further 10 points between himself and Vettel, leaving the gap between the two at 40 with six races to go.

"Red Bull was a real factor in Singapore," said Wolff, when asked about the team's form by Autosport.

"And [it would be good] if they could play more of a role until the end of the season.

"It is good to have them in the mix, it is good for the fans and for the racing. We enjoyed it.

"Mexico will be the next one where on paper they should be really quick, but who knows what happens in Sochi and Suzuka."

Horner also said Hamilton's drivers' championship lead was commanding, but that it was still too early to write off Vettel's chances altogether.

The German won four championships with Red Bull, including in 2012 - when he staged a late-season comeback to defeat driver Fernando Alonso, having been 42 points behind the Ferrari driver during the mid-season break.

"Usually he's very good under pressure," Horner said of Vettel. "So he certainly won't give up.

"He was 40-odd points down before, I think, in 2012.

"It looks like Lewis is in the driving seat now, he's just got to be consistent to the year's end. It's certainly going to be an uphill battle [for Ferrari] to get themselves back into it.

"Ferrari has a very quick car, there's still six races to go, 150 points available. Anything can still happen, but Lewis is over a weekend and a third place ahead. He looks in good shape."