Trainer Paul Nicholls said Kauto Star, whose participation in the Gold Cup was in jeopardy following a schooling fall a fortnight ago, had returned from the race unscathed.
He said: "He's absolutely fine.
"Ruby wasn't happy after he'd jumped a couple of fences and we said if he wasn't happy to pull him up, and he's done the right thing.
"There's obviously something tweaking him."
Following the race he tweeted:
KAUTO STAR FINE.