The number of Super rugby teams is about to decrease but former Blues coach Sir John Kirwan believes the size of squads needs to increase.
Under the new 15-team, three conference format, franchises will play 16 regular season matches with eight of those being against teams within their conference - that means home and away matches for the five NZ franchises.
The New Zealand derbies have been a highlight of the competition and Kirwan says while more local matches is good, they take a much greater toll on the players.
"If the competition just gets harder I think it might be costly from a player attrition rate but I don't think that's a concern, we just have to increase our squad size which will help retain our players.
"I think it's a real positive, us playing each other in these derbies is what makes us great," Kirwan said.
Kirwan believed the cull of two South African and one Australian team was necessary but believes there are still areas of improvement in the playoff format.
The new format is largely similar to the old one - the three conference leaders will be guaranteed a home quarterfinal while the fourth best team will also play their quarterfinal at home.
"I prefer for the public a really simple look at it which is the top eight qualify and that's it.
"The Blues (last in the New Zealand conference) right now are ahead of the best team in Australia (the Brumbies) but would miss out on playing in the finals so for me the top eight on merit should be in the finals."
Kirwan said the under fire Sunwolves deserve to be in the competition at least until the 2019 World Cup in Japan to allow more growth in the region.