Crotty and Proctor are two of 25 All Blacks coming off contract in 2019, with plenty emerging as targets for offshore clubs.
New Zealand Rugby (NZR) chief executive Steve Tew admitted to Fairfax in August that retaining all of the players that are off contract would be a challenge, especially without the Lions tour as a bargaining chip.
“Inevitably, there will be some players who we don’t keep who are currently in that jersey,” Tew told Fairfax.
26-year-old Proctor won his first All Blacks cap against Japan last year after five seasons with the Hurricanes.
He scored a test try on debut and Boyd has been vocal about his opinion of the midfielder, rating him as “the best centre in New Zealand” in an interview last year.
30-year-old Crotty is heading towards the tail-end of his career and is an outside chance to last another World Cup cycle.
The 43-test veteran has become a linchpin in the All Black midfield since his debut in 2013, becoming a regular starter after the 2015 retirement of longtime centre Conrad Smith.
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