The R&A has agreed that the two-shot penalty imposed on Li Haotong at the Omega Dubai Desert Classic was correct.
Li, playing in the final group alongside runaway winner Bryson DeChambeau, was lining up a short putt for birdie on the 72nd green with his caddie standing behind him.
The defending champion's caddie, Mike Burrow, moved away just as Li began to take his stance, and he rolled in the putt for what he thought was his 71st and final shot of the day, earning him a share of third place on 16-under par.
But European Tour officials found Li in breach of a new ruling, introduced at the turn of the year, that prevents caddies from helping their players with alignment.
The birdie-four was changed to a bogey-six shortly after the close of play, dropping him outside the top 10 and costing him over 80,000 euros in prize money.
The ruling did not sit well with many observers, including Lee Westwood and Matt Wallace, while Justin Rose's regular caddie, Mark Fulcher, described the penalty as "a farce".
European Tour Chief Executive Keith Pelley said whilst correct, the ruling against Li was still "grossly unfair" and he has contacted the R&A to voice his displeasure.
Responding on Monday, R&A chief executive Martin Slumbers said: "We have reviewed the Li Haotong ruling made by the European Tour referees and agree that it was correct.
"There has been some misunderstanding of the new Rule and I would point out that it is designed to prevent any opportunity for the caddie to stand behind the player as he begins to take his stance.
"Whether the player intends to be lined up is not the issue.
"We appreciate that it was a very unfortunate situation yesterday and I completely understand Keith Pelley's concerns when a Rules incident occurs at such a key stage of a European Tour event but there is no discretionary element to the Rule precisely so that it is easier to understand and can be applied consistently.
"We are continuing to monitor the impact of the new Rules but I made it clear to Keith that our focus is very much on maintaining the integrity of the Rules for all golfers worldwide."