"We were apprehensive right from the start and didn't play as a team. You're not going to win games off one or two individuals and the disappointing thing is I know we're better than that," he said.
"We ran the ball too much as individuals, didn't stick to our game plan and couldn't put anything on target in the attacking circle. Great Britain worked hard, were tougher physically and outmatched us today. They deserved to win.
"We need to go away and reflect on how we played tonight. We still have a bronze medal on the line so we can either feel sorry for ourselves and come away with nothing or get better and make sure we win bronze."
It was an up tempo start to the game with both sides going end to end and creating chances on attack.
Great Britain made the most of a penalty corner in the 21st minute when Alex Danson pounced on Sally Rutherford's initial save and flicked into goal.
New Zealand poured the pressure on in the third quarter but weren't able to capitalise on any of their half chances.
Great Britain extended their lead in the 47th minute when a defensive blunder gave away a penalty stroke which Helen Richardson-Walsh slotted past Rutherford.
Four minutes later it was another penalty stroke which allowed Danson to score her second goal of the match and seal the result for Great Britain, who now will contest their first ever gold medal match.
In today's other semi final, the Netherlands progressed to the gold medal match after defeating Germany 4-3 in a penalty shoot-out after the game was drawn 1-1 at fulltime.
The result gives the Dutch the chance to defend their Olympic title after they won the London 2012 gold with a 2-0 result over Argentina.
