Gayle was fined $10,000 by his Big Bash League side Melbourne Renegades for his on-air mid-match comments to Channel 10 journalist Mel McLaughlin during a BBL match.
"I have played against Chris for a long time, since I started really, and that behaviour is fairly expected," Watson was quoted as saying by 'Daily Telegraph'.
"People who know Chris Gayle will know those are the sort of things he can do at times, and at an inappropriate time, obviously it gets him into a fair bit of trouble," he added.
Gayle invited controversy after he said he was happy to be interviewed by McLaughlin "just to see your eyes for the first time" during his sides' win over the Hobart Hurricanes on Monday.
"Nice, so hopefully we can win this game and we can have a drink after," he had said.
"Don't blush baby," the Jamaican added, prompting McLaughlin to shake her head and reply, "I'm not blushing."
Watson made it clear that Gayle had overstepped the mark with McLaughlin, and supported Cricket Australia's plans to make sure this summer would be Gayle's last.
"There is no doubt people have always loved coming along and watching him (Gayle) play because of the entertainment he can certainly provide.
"But there is always a line outside the game of cricket as well.
"In the end the people love the entertainment part of cricket, but there's also a respect, that part of playing the game on and off the field in the right spirit.
"In the end there are people who will be making decisions either way (about Gayle's return). It's not just what you bring on the field, it's what you bring off the field as well, which is as important," Watson said.
Gayle later apologised for his offence, saying it was a "simple joke".
Image: A video grab of Chris Gayle flirting with journalist Mel McLaughlin.
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