Sportal.co.nz 31.Mar.2013Getty Images
The second rower had to be helped from the field and was wearing a moonboot when he left Westpac Stadium for scans on Saturday evening.
He was one of several players left feeling the effects of a bruising encounter that the Hurricanes never really dominated to the extent the scoreline suggests.
Victor Vito (tight calves) and Dane Coles (hand) also left the field early but coach Mark Hammett believed those were less of a concern than Thrush's ankle.
The Kings didn't escape either with Kiwi-born back Hadleigh Parkes suffering a suspected broken arm around 10 minutes before half-time.
Hammett would have been the happier of the two coaches at the break as his side led 29-16 and had already wrapped up the four-try bonus point.
But instead of closing the match out early in the second half and building on the platform they had laid the accuracy dropped as they started pushing passes and giving away penalties rather than showing the patience they had displayed in the opening 40 minutes which led to tries for Ben May, Conrad Smith, TJ Perenara and Thrush.
"Those four tries were four really well constructed tries in that first half. We did what we wanted to do. In the second half we attempted to do that but we were just a bit inaccurate," explained Hammett.
"Sometimes it happens when you get leads and you feel like you're well on top of it, that you don't quite put the screws in.
"The attitude was there it was just some individual skills around passing, catching, that sort of stuff.
"I'm happy with the lads but we're going to have to be a lot more accurate than that."
Smith admitted at one stage memories of the loss to the Cheetahs last season started to surface. In that game the Hurricanes led 32-11 after scoring four first-half tries and went on to lose 47-38.
"[That] was an afternoon kick-off and high scoring and we ended up losing it. We can take a bit of confidence that we hung tough," he added.
"There was a good five maybe 10 minutes it felt like 'oh'. We were only up by six and they were pounding the line. But we came through that and then scored a couple more tries [through Brad Shields and Alapati Leiua]. It was good to come out the way we did in the end."