Motor racing-Horner says Red Bull's constructors' crown means the world

(Reuters) - Red Bull boss Christian Horner said winning the Formula One constructors' title had a special significance because of the tough times the team had been through since their previous success.

The team clinched their fifth constructors' title, and first since 2013, when double world champion Max Verstappen won the U.S. Grand Prix in Austin, Texas, on Sunday and Mexican Sergio Perez was fourth.

The championship ended a record run of eight in a row for Mercedes.

"It means even more (than previous ones) because we’ve had the tough years. We’ve had to keep picking ourselves up, dusting ourselves, coming back and coming back," Horner told Sky Sports television.

"And we’ve done that. So the hard work and the blood, sweat and tears that have gone into this, this one just means the world to us."

Red Bull entered the sport in 2005 and, with top designer Adrian Newey on board, took four successive drivers' and constructors' titles with Germany's Sebastian Vettel from 2010-13.

Then the rules changed, with a V6 turbo hybrid engine replacing the much simpler and fuel-thirsty V8s, and Mercedes made big gains while Red Bull's then-partners Renault struggled.

While Verstappen won his first drivers' title last year, Mercedes kept their constructors' crown.

This year, with another rules rewrite, there has been no contest. Red Bull have racked up 15 wins in 19 races with three to come.

"Credit to Red Bull, they’ve done a mega job all year," said Mercedes team boss Toto Wolff. "Max was really strong so them winning the constructors’ championship today is what they deserve."

Verstappen also equalled the Formula One record for most wins in a single season - the 13 previously achieved only by Vettel and Ferrari great Michael Schumacher - and