"Obviously not being involved in previous World Cup cycles, and to be this close - to be 90 minutes away from the World Cup - it's hands-down the biggest," he said.
Since Anthony Hudson took over as coach in 2014, Boxall has played more games than Reid and Smith combined. In fact, only Michael McGlinchey has played more often in the outfield under Hudson, making the towering defender as close to a fixture in the side as is possible in a three-and-a-half-year period during which 49 players have donned the white shirt in 26 matches.
After playing his part in Saturday's clean sheet which has kept this tie well and truly alive, Boxall knows another busy night awaits at Lima's Estadio Nacional.
"We expect a fair bit of the same," he said.
"But with their raucous crowd roaring them on, they'll come with a little more intensity. We have to be that much more switched on and clued in and just stick to our game plan."
New Zealand are huge underdogs with practically everyone in the footballing world expecting Peru to advance, but Boxall and his team-mates are unperturbed by that. In fact, the belief in the side is palpable.
"Everyone has really bought into the system," said Boxall.
"If we don't make it to the World Cup next year, we're going to be so disappointed."
