Christian Horner found it remarkable that the Mercedes cars drove much faster than the Red Bull cars on the straights of Istanbul Park this weekend.

The Red Bull team boss had no explanation for the big difference in speed.

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"They were very fast this weekend," Horner said of Mercedes in Istanbul.

"If you look at Lewis today, he was running 15 to 20 km/h faster than us on the straight. We will have to find a little bit of extra speed. Maybe they were running in a different set-up than usual."

Earlier this year, Red Bull already questioned the legality of the Mercedes engine when it was suggested that the German team could extract extra power from the power source by using a trick with the so-called intercooler.

"To be clear, we didn't protest at the time, just asked questions," Horner continued.

"Not only did Red Bull do that, but other teams also asked questions. It is up to the FIA ​​to clarify that."

Sergio Pérez and Lewis Hamilton battled each other for laps at Istanbul Park.

Sergio Pérez and Lewis Hamilton battled each other for laps at Istanbul Park.

Photo: Getty Images

Horner enjoyed battle Pérez and Hamilton

Although Max Verstappen took over the World Cup lead from Lewis Hamilton with his second place, Horner had especially enjoyed Sergio Pérez.

The Mexican managed to keep Hamilton - partly due to a nice fight - behind him.

"He raced against Lewis as hard as Max would have done. It was fantastic to see Lewis almost push him into the pits, but 'Checo' still held up."

The Formula 1 season will continue in two weeks with the United States Grand Prix in Austin.

There are still six races on the calendar.

See also: World Cup leader Verstappen: "Given the circumstances, very good result for us"