"It's really unfortunate, especially for Winston," said Hudson. "He's our captain, our leader and a really important player for the group. But he plays in one of the most demanding and physical leagues in the world and injuries can happen at any time. We can't be going into big games without a back up plan in case we lose important players."
New Zealand Football gave Reid as much time as possible to recover from his hamstring strain, which he picked up at the beginning of the month. But the injury has healed slowed than expected. There was also a possibility that Reid could join the team in a non-playing capacity but that was ruled out by NZF.
It continues an unfortunate sequence for Reid, mostly due to untimely injuries. He has only played once for New Zealand since October 2013 (in the 3-1 loss to Uzbekistan in Hudson's first match in charge) and has appeared in just 12 of 30 All Whites games since his head turning performances at the 2010 World Cup.
"We need to develop alternatives so it's not a major panic if such situations arise," said Hudson. "That is the crucial aspect; knowing if we lose a key player, another can step in."
While yesterday's news wasn't unexpected, it's a blow for this young New Zealand side. With Tommy Smith also unavailable, it means there is a lack of experience in the centre of defence.
That could be crucial against the pacey Korean attack, especially with green horns Storm Roux and Deklan Wynne in the fullback positions.
It's now likely that Phoenix defender Michael Boxall and debutant Themistoklis Tzimopoulos will form the central defensive pairing.
The 26-year-old Boxall has played nine times for the All Whites, since making his debut against China in 2011. Tzimopoulos has yet to represent New Zealand but has almost 100 games in the Greek Super League behind him.
Meanwhile, the All Whites squad had a day off training today, after a series of tough sessions in the last few days. The players had meetings and video sessions and some of the new faces were measured up for their uniforms and off field kit.
Winston Reid
-Made his debut in May 2010.
-After a starring role at the 2010 World Cup, has only played in 12 of the last 30 All Whites matches.
-Has been unavailable for six of the last seven international fixtures.
*Michael Burgess travelled to Korea with assistance of ASB, the principal partner of New Zealand Football.