The disgraced ex-Australian captain and vice-captain are barred from playing in the BBL as part of their 12-month bans for their roles in the Cape Town ball-tampering scandal.

But the Cricket Australia sanctions allow the pair to play club cricket abroad and both have signed up to the Canada tournament.

Watson is already on the record branding the penalties, which also include an additional 12-month leadership ban for Smith and a lifetime leadership ban for Warner, as "extreme".

And on the same day Smith marked his cricket comeback with a half-century for the Toronto Nationals, his former teammate questioned the logic of Australia's two most high-profile players helping boost another country's competition.

"The thing that just disappoints me about the whole situation is now Steve Smith and Dave Warner are over promoting other tournaments by playing in them," Watson said.

"I understand the rulings that happened at Cricket Australia, the 12-month bans and all the stipulations they put around that.

"But for them to have the opportunity to go and promote other tournaments, I'd prefer if they're going to do that and have access to do that (that) they have access to promote the Big Bash, for example.

"At the moment we've got a few world-class players and we'll continue to discover those but they don't just fall out of trees.

"That's why Steve and Dave are such an integral part to Australian cricket, especially in the shorter format as well with the World Cup coming up."

Watson himself has no interest in heading to Canada, prioritising a break after the Pakistan Super League and Indian Premier League.

But at 37 he continues to defy age, on Friday re-signing with Sydney Thunder for a further two seasons under new coach Shane Bond.

Thunder also announced the signing of 25-year old allrounder Daniel Sams.

Australian Associated Press