Wallabies great David Campese has described the expanded Super Rugby format as "ridiculous, an absolute nightmare and not really viable".

He expressed major concerns about player welfare as the three new teams take the championship to 18 teams and a regular season of 135 matches.

Campese lamented the lack of a Pacific Islands side and predicted financial struggles for teams.

"A couple of teams in Australia are running out of money and are up against it with other major sports. You have to win, but you have to win with a bit of style to get people to come back and watch, which is frustrating," Campese told Planet Rugby.

"It's ridiculous. They're trying to create something that's not really viable."

"Realistically it's just going to be an absolute nightmare. There doesn't seem to be any thought going into the players' welfare about the travelling. No one seems to know. It's an absolute mess.

"Money's great, but on the other hand if you want to [increase the] competition why not bring in the Pacific Islands as well? Why have you got to go to Japan?

"It's a total mess and I think something major is going to happen to make them change their mind."

He believed the addition of the financially struggling Kings franchise in South Africa was " a disaster" and was concerned that the Japanese Sunwolves weren't well enough prepared.

"[The organisers] maybe should have had a year off to get the best players and formats in place. The Japanese team are going to have, I think, half a team of foreigners – how is that good for Japanese rugby?" Campese asked.