Former World Cup commentator McKay publicly sparked the rumour mill this morning, citing a source who said Williams' withdrawal was imminent.
McKay, the former TV3 sports anchor and rugby editor, reckoned: "How long before Ngani Lauampe is on the plane?"
"I trust my source absolutely. Watch this space," McKay told Newstalk ZB's Martin Devlin.
"It's more than an injury watch day … it's a day-to-day proposition. I think we're going to hear something break."
Players who are replaced can take no further part in the tournament. Both Williams and Laumape are second five-eighths not known for playing other positions at test level.
Laumape has kept up his solid form while playing for Manawatu in the Mitre 10 Cup. Yesterday he bagged two second-half tries to see the Turbos overcome a 26-7 halftime deficit and deny Southland what would have been their first win in three years.
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