(Reuters) - The growing number of leading golfers withdrawing from the Rio Olympics has disappointed the sport of squash, Professional Squash Association (PSA) chief executive Alex Gough has said.

Squash was among the sports short-listed for possible inclusion at the 2020 Olympics but failed to make the final list of five, with golf selected to feature at the Games in Tokyo.

The world's top four players -- Jason Day, Dustin Johnson, Jordan Spieth and Rory McIlroy -- have pulled out of the Games citing health concerns from the mosquito-born Zika virus.

Australia's Adam Scott, who will also skip the Games, told Reuters a year ago he considered Olympic golf to be an "exhibition" event, with other sports much more deserving of Games exposure.

"It has been intensely frustrating. Quite honestly, it was almost predictable. Very early on Adam Scott said Olympic golf was, in his words, going to be an exhibition event," Gough told British media on Tuesday.

"That basically showed everyone else that it was not held in as high esteem by the top players as it should be. You've got guys saying it won't count as their pinnacle, and that's the most disappointing thing to the squash-playing community."

Rio will mark the return of golf to the Olympic fold for the first time since 1904.

Squash, played in more than 185 countries, has made great strides in modernizing the sport, with the PSA taking the game to iconic venues such as New York's Grand Central Station.

(Reporting by Ian Rodricks in Bengaluru; editing by Ken Ferris)