The Barbury Castle trainer has earmarked the Group Two prize on October 17 as the next target for the progressive Planteur gelding.
Having run a respectable race in defeat in the Ebor at York on his penultimate start, Trueshan bounced back to winning ways in a conditions race at Salisbury last time out.
King said: “All being well, the plan is to go to Ascot on Champions Day for the Long Distance Cup.
“He came out of the race very well and he had an easy week or so before we start building him back up for Ascot.
“He ran very well in the Ebor – and it was a good, solid performance at Salisbury to give everything bar Withhold seven pounds.”
While it will be the first time Trueshan – who tasted Listed glory at Haydock earlier in the season – has performed at Group level, King believes it is the correct path to take.
He said: “This looks the right route to go. It is a big step up in class, and we are very much on a learning curve with him.
“We want to find out where we could potentially go with him next year.”
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