The 31-year-old, however, is not expected to require surgery and should be fit for the tail end of the Super Rugby season, with the Crusaders leading the competition and strong favourites to win a third-successive title.
“The good thing is it doesn’t require surgery, so it will be a good rehab process,” Crusaders assistant coach Jason Ryan told reporters. “It’s obviously a relief for everyone.
“It was touch and go there for a bit – get him back in a month, all going well.
“He’s got a good rehab plan for the next four weeks and, all going well, that’s when he will return to play.”
Franks, a cornerstone of the All Blacks’ scrum since his 2009 debut, was injured in the Crusaders’ 36-14 victory on April 6 over the Brumbies.
The tighthead prop wrenched his shoulder and uncharacteristically pulled out of a scrum just before it engaged, saying “nup” and immediately trudged towards the sidelines.
Crusaders coach Scott Robertson had said last week that Franks needed a second scan, which caused some consternation among All Blacks fans ahead of the Rugby World Cup later this year in Japan.
Franks, with 106 caps, was a core member of the side who won the World Cup in 2011 and 2015.
All Blacks coach Steve Hansen has capable replacements. Nepo Laulala, with 17 caps, had cemented himself as first choice when Franks had 2017 surgery on his achilles.
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