The Shamardal colt suffered the first reverse of his career as he could finish only third behind Kameko and Wichita, beaten a length and a quarter in total, in the Newmarket Classic.
Pinatubo won each of his six juvenile outings and boasted a rating of 128 going into the Guineas, which Kameko won in a new course-record time.
Appleby revealed Pinatubo had lost three kilos on Saturday
Appleby immediately pointed to the St James’s Palace Stakes at the Royal meeting as Pinatubo’s next target and is not concerned about turning out again just 14 days later.
He told Racing TV’s Luck On Sunday programme: “First signs are very good, he ate up last night and he’s been out and had a walk this morning. He lost three kilos for the race there, so we’re very pleased with him.
“You wouldn’t want to be losing too much more than that. I felt confident going in there his fitness levels were where they needed to be to compete and he showed that in the race, so I’m pleased.
“He’s come out of the race well, he’s eaten up and we can hopefully head on to Ascot, that’s the main thing.
“He ticked every box, even throughout the race I was happy. At home he wouldn’t get you excited in the mornings so I was pleased he was up there travelling and showing all his usual enthusiasm.
Sheikh Fahad gave his reaction to Kameko's win to Nick Luck
“Much as I feel we saw the mile out, I think we were outstayed by two horses over that trip on the day.
“It’s an unprecedented year this year in where we are and trying to make a bit of ground up, but he gives himself every opportunity to back up quickly because he conserves energy from one race to the next.”
As for the winner, connections have yet to commit to a target, but trainer Andrew Balding admitted in the aftermath that a crack at the Investec Derby would be on his radar, although the colt’s stamina is not assured.
Sheikh Fahad al Thani, in whose Qatar Racing colours Kameko competes, would also be open to running at Epsom on July 4, but will take his time in making a decision.
He said: “It’s unfortunate I couldn’t be there (due to racing taking place behind closed doors), but it was beautiful to watch.
“I think we should have a little think about it. I’ve watched the race a few times now and, to me, he wasn’t stopping at the end.
“His sectionals show that he hit the line and he hit the line well, so it does give us hope to go for the Derby. It is the greatest race in racing.
“He is a beautiful horse and the thing with him is he improved from race to race last year and he did something that (former Qatar Racing star) Roaring Lion didn’t do which was win a Group One as a two-year-old and now he’s won a Classic as well.”
Sheikh Fahad is a director of sponsors Qipco and he added: “It is the race I personally wanted to win more than anything – it was the first race I attended.”
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