Sainz and Verstappen impress Red Bull boss Horner

Christian Horner says Toro Rosso's Carlos Sainz Jr and Max Verstappen are staking their claim to become future Red Bull drivers.

Red Bull boss Christian Horner believes Toro Rosso duo Carlos Sainz Jr and Max Verstappen are driving their way into contention for a spot on his team.

The pair are in their rookie season after being promoted from the Red Bull junior programme, and have impressed thus far.

Sainz scored points in four of the first six races of 2015, while Verstappen - the youngest driver in F1 history - took fourth at Hungary last time out.

"They've both driven very well this year," Horner told Autosport.

"They've been one of the highlights of the season so far, which just proves that giving young talent a chance pays off."

Asked if the pair could be considered for future Red Bull line-ups, Horner replied: "Very much so.

"The programme has produced some great talent in recent years, and shows we're not short of talent across the two teams."

Horner also had words of praise for Red Bull's current line-up Daniil Kvyat and Daniel Ricciardo, whom he believes have formed a strong partnership.

"They just need to continue the way they are, to keep pushing each other," Horner said.

"What we saw in Monaco was unprecedented in comparison to other team-mates where Kvyat gave up position to Ricciardo to have a go at a podium.

"It was on the understanding if Daniel couldn't get into a podium position then he would give it back, which he did at the last corner.

"That shows the drivers are working extremely well within the team, and for the team. They get on very well. They both grew up in the junior programme, so they know each other pretty well.

"There is a small age gap between the two of them, but it's a very strong dynamic. They're as strong a pairing as we've had."