The Red Bull team principal saw Sebastian Vettel become the sport's youngest ever four-time champion with his 10th win of the season at the Indian Grand Prix on Sunday, a result which also secured the Milton Keynes-based outfit their fourth manufacturers' crown in a row.
With sweeping regulation changes coming in from 2014 and both titles already in the bag, Red Bull could be forgiven for taking their foot off the gas over the closing races in Abu Dhabi, the United States and Brazil.
But with momentum such a key ingredient in F1, Horner is refusing to allow his rivals to steal a march.
Asked if it really mattered to him whether a Red Bull took the chequered flag over the final three rounds, Horner said: "Absolutely. It's like three FA Cup finals. We want to win every race."
Certainly both of Red Bull's drivers have plenty of reason to hope there are more wins to be had for the peerless Adrian Newey-designed RB9 between now and the end of the season.
Mark Webber - who retired from Sunday's race with an alternator problem - has yet to win a race in 2013 and will leave the team at the end of the season for a new challenge with Porsche in sports cars, so his motivation to sign off with a victory will be high.
Vettel, meanwhile, has now won six races in a row in the second half of 2013 and on current form it is not inconceivable that he could equal Alberto Ascari's long-standing record of nine consecutive race wins, set across two seasons in 1952 and 1953.
Certainly if anyone can threaten Ascari's record it is Vettel, who on Sunday became only the fourth man in the sport's history - after Juan Manuel Fangio, Alain Prost and Michael Schumacher - to become a four-time champion.
At the age of just 26, Vettel is six years younger than Schumacher was when he won a fourth title in 2001, 12 years younger than Prost when he achieved the feat in 1993, and 19 years ahead of Fangio, who was 45 when he reached that number in 1956.
Fangio's final tally of five titles will be in Vettel's sights when the 2014 season gets under way, and he will no doubt fancy his chances of eventually eclipsing fellow German Schumacher's outright record of seven drivers' championships.
Horner warned Vettel will need to keep a strong team around him if he is to one day challenge Schumacher's tally, although on raw talent alone he has no doubt the racer from Heppenheim has got what it takes.
"His win record is quite incredible," Horner told reporters.
"But there are so many things in this sport that determine that. It depends on being in the right machinery as well.
"But from a skill point of view there is absolutely no reason why not.
"I think Sebastian has grown this year. The way he's driven, the level at which he's delivered, it's been his best ever year. He's raised the bar continually.
"He is now by rights one of the all-time greats. He joins a very select few but it needs everything to work in harmony.
"You can have the best driver in the world or the best designer in the world, but if you don't have the right team and work as a team it will never work."