Sam Cane says New Zealand Rugby should reconsider their rules which prohibit the selection of overseas players for the All Blacks, as he started a short stint with Japanese side Suntory Sungoliath.

The New Zealand captain is among several of the sport's stars, including World Player of the Year Ardie Savea and South African flyer Cheslin Kolbe, who will play in Japan's League One this year, enticed by high salaries and a relatively compact rugby calendar.

While Cane will not miss any internationals during his brief sabbatical, other All Blacks like Richie Mo'unga have signed multi-year deals in Japan that effectively rule them out of selection unless New Zealand's governing body changes its rules.

"A lot of the Springboks have shown the ability to play in League One and go back to international rugby fairly quickly and continue to play their best," Cane said at a news conference in Tokyo when asked if it was time for a rule change.

If New Zealand players returning from overseas stints could likewise show it has not been detrimental to their performance, then "maybe that conversation can be had", Cane said.

Outgoing All Blacks coach Ian Foster (above) has previously said changing the rules would be a "disaster" for rugby in New Zealand as it would draw talent away from its Super Rugby competition and stifle domestic player development.

Currently the NZR's selection policy is the same as in Ireland, where those playing outside the country aren't eligible for the national side.

Cane, who was sent off in last month's Rugby World Cup final loss to South Africa, said he had held talks with new All Blacks coach Scott Robertson but would not be drawn on whether he expected to keep the captaincy.

"I know the All Blacks coaches will be keeping an eye on some of us boys over here, so sole focus will just be to play well and try to improve," he said.

While Japan was once seen as a destination for overseas players in the twilight of their careers to cash in at clubs without the strict salary caps seen in other leagues, luring top talent in their prime is giving it more cachet.

"It's grown immensely. It's much more competitive," said Kolbe, who signed for Suntory alongside Cane. "Everybody is up to standard now. That's the exciting thing."

Suntory lost in the semi-finals of last year's competition to eventual winners Kubota Spears, who boast New Zealand hooker Dane Coles, Australian playmaker Bernard Foley and Welsh full-back Liam Williams among their ranks this season.

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