Paul Nicholls reports Kauto Star has taken a "big step forward" and "a bit of the old swagger returned" after watching him work at Ditcheat.
The legendary steeplechaser fell when schooling at the champion trainer's base last week and while no serious injury was suffered, connections revealed he was only 50-50 to bid for a third Gold Cup.
However, Nicholls expressed his satisfaction after seeing the 12 year-old enjoy a canter with stablemate and fellow Gold Cup hope What A Friend.
"Kauto had his physio this morning and had an hour on the walker, and you could just tell that he had more of a buzz and a spring in his step, and that a bit of the old swagger had returned," Nicholls said in hisBetfair column.
"So we decided to send him out second lot and he did a strong canter over ten furlongs with What A Friend, and delighted us.
"And when Clifford (Baker, head lad) pulled up and said 'big step forward', he didn't need to add anything. I could simply tell by the smile on his face.
"I cannot tell you how massively relieved I am to see Kauto progressing and going forward.
"Don't get me wrong, or carried away, because he is not there yet.
"Not at all, and things can change daily. But this was a step in the right direction and I'm much happier, I can tell you.
"We were going to give him Sunday off but I have decided to keep the momentum going and he will have another canter tomorrow.
"I just hope that Clifford and I are as pleased with him tomorrow, as we are right now."
Earlier, Nicholls admitted he faced "the biggest decision I've ever had to make" regarding whether Kauto Star would be allowed to line up in the blue riband in less than a fortnight's time.
No final decision will be made on his Prestbury Park participation until next weekend.
"It's getting better and better every day," Nicholls said.
"He's never taken a lame step, he's never been off his grub, he looks great and he's cantered every day since it happened.
"He can't talk to you and tell you exactly where it (pain) is, it's impossible to tell. Clifford can just tell by riding him.
"Every day he comes back from work, he always has a roll. He hadn't done that until yesterday morning, so that's a good sign. We're moving forward.
"The idea is to work him hard as normal next week and next Saturday he is due to do a strong piece of work, his last serious gallop, with Big Buck's.
"There are no fitness issues here, we haven't missed any work and he was fit and well.
"Next Saturday will tell us, then I'll have a discussion with Clive (Smith, owner) and Clifford. We'll all have a little input and see if we can come up with the right decision.
"It's a difficult decision, probably the biggest decision I've ever had to make.
"We've got it right so far this season, we want to try and get it right again."
