The veteran captain, playing in the tournament for a 10th time, scored a converted try in the final seconds to give the All Blacks an undeserved 17-12 win over Croatia, who led 12-10 with two minutes remaining.
Croatia, with seven New Zealand-born players in their ranks, shocked the Commonwealth Games sevens gold medallists by taking a 12-0 halftime lead through tries by Reon Graham and Michael Lunjevich. Two scores by sevens expert Dallas Seymour narrowed the gap and Croatia let the New Zealanders off the hook when they ran a penalty with two minutes left instead of going for three points.
"We knew it was going to be tough - we should have lost," admitted Rush. "The Hong Kong Sevens could have been over for us before they began."
While New Zealand were struggling in Group D, the favourites and eight- time winners Fiji were strolling to a 63-0 win over Thailand in Group A.