Sebastian Vettel's chances of leaving Singapore with the Formula One world championship lead are in tatters after a dramatic Turn 1 collision involving teammate Kimi Raikkonen and Red Bull's Max Verstappen.
Vettel stormed to pole on Saturday with Hamilton all the way down in fifth with the German safe in the knowledge that he would regain the lead in the Drivers' Championship with a fifth victory at Marina Bay.
"I don't know [what happened], I didn't see that much". We'll see what happens.
Verstappen blamed Vettel, but none of the drivers will face further action.
"It's a long race but we are on the wrong side of the track so that doesn't help. I think right now I'm starting to cool off".
A replay showed fluid streaming out of Vettel's damaged sidepod after Turn 1 and it is likely it caused him to lose the rear of his auto and hammer his Ferrari against the concrete wall.
After a few laps behind the safety vehicle, the race resumed for real on lap 7.
Asked whether Ricciardo could have won if not for the gearbox problem, Horner said: "We certainly could have been closer and put a bit more pressure on".
Through the first two sessions of qualifying, it had looked like a stroll to pole for Max Verstappen but he was unable to find enough time when it mattered most to overhaul Vettel - the Dutchman forced to settle for the second place.
It has been a frustrating season for Alonso, who had to retire for the ninth time. Hamilton just drove too well for either Ricciardo or Bottas to be able to take the win off him.
The remaining cars had to pass through the through the pit lane behind the safety auto as the marshals cleared the debris at turn one.
The safety auto came out again, after Marcus Ericsson's Sauber stalled on lap 39.