Christian Horner says Max Verstappen is doing a "remarkable" job for Red Bull, amid the team's attempt to make further inroads into Mercedes and Ferrari's F1 advantage.

Verstappen is currently behind only the Mercedes drivers in F1's standings after the opening three rounds of the 2019 season, despite the nascent Red Bull-Honda partnership not yet being on a par with their big two rivals.

"He's done a remarkable job. During the course of last year, he really selected another gear and pretty much since Montreal onwards," Horner told Sky Sports F1.

"He's very much at the top of his game and enjoying the position he's in."

After Verstappen finished fourth in China last weekend, Horner also told reporters: "He's driven three very strong grands prix this year.

"He was obviously unlucky not to be on the podium in Bahrain and had a go at Sebastian [Vettel] here after the second stop and drove a very mature race to bring it home fourth."

F1 Drivers' Championship top five 1. Lewis Hamilton Mercedes 68 points 2. Valtteri Bottas Mercedes 62 points 3. Max Verstappen Red Bull 39 points 4. Sebastian Vettel Ferrari 37 points 5. Charles Leclerc Ferrari 36 points

The Red Bull boss added: "It's about points accumulation at this stage. It's still not that big a gap to the guys ahead, he's still third ahead of both Ferrari drivers in the championship at the moment, and there's a still long, long way to go.

"So it's important you don't give away too much ground at this stage of the year."

Verstappen is now in his fifth season of F1 but is just 21 years old, and Horner added: "The exciting thing about him is that he will only develop and get better from here.

"It's exciting times for Formula 1 to have the likes of Max, the emerging talent of Charles Leclerc, and hopefully we'll see Pierre Gasly join that group as well.

"It's an exciting time that there's another generation that is coming to the forefront."

Horner on Red Bull's new era

While acknowledging they still have improvements to make on their RB15 chassis and Honda engine, with upgrades expected for the forthcoming races, Red Bull's move to effective works status with the Japanese manufacturer has allowed the team to take more control and direction over engine and fuel development.

"It's a totally different relationship," said Horner. "With our previous supplier, it was very much a customer-driven scenario where we were allowed to look at two candidates a year for fuel upgrades.

"This is constant evolution and development. ExxonMobil working with Honda are making great gains.

"Fuel is such an important factor in the development of these engines now that there's real benefit and real lap time that is on the table that fuel companies are responsible for."

Asked about Honda's impact on the team, Horner added: "It's been a real injection of enthusiasm, passion and shared goals and visions. We are very happy with how the relationship has started and what's in the pipeline."

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