England took out the first Test in Hull despite falling behind 10-0 in the first half.
“The four players on the bench really turned that game for us,” McNamara said.
“They really got us going forward and that’s what benches are there for – to add to your team, not just try and survive during that period when they’re on. Those players certainly added to us.
“Tom Burgess was incredible tonight, he should be one of the stories of the game.
“I wouldn’t say he was unstoppable but they certainly found him so tough to deal with on occasions.”
In the second half the home team were dominant and shut down the Kiwis well.
A final try to Sean O’Loughlin wrapped the game up.
“In the first half we put ourselves under a lot of pressure, we looked out of sorts,” McNamara said.
“But we started to come back towards the back end of the half, that really set ourselves up for the second and we finished the game very strongly.
“I had to support the players’ feelings at half-time. Physically we weren’t in the game and we needed to change that. Thankfully we did.”
McNamara believes his team can play better in the next two Tests.
The two countries meet again in a week’s time at the Olympic Stadium in London.
“There is lots to work on for next week, both teams can perform a lot better than that,” he said.
“These are tough games though, and with only a six-day turnaround, recovery is the number one priority right now.”