Wellington: New Zealand's Brendon McCullum will miss Thursday's third and final Twenty20 international against Pakistan, having missed the first two with a back injury, New Zealand Cricket said on Wednesday.

With New Zealand winning both the Twenty20 matches in Auckland and Hamilton, the Christchurch match has been rendered inconsequential, prompting the selectors to provide McCullum further rest ahead of the two-match Test series against Pakistan starting on Jan 7, followed by six one-day internationals against the same opponents.

"Brendon got through the fitness test well and we are pleased with the progress he has made," selector Glenn Turner said in a statement.

"Although the signs are good the selection panel think the sensible approach is to rest Brendon for the final Twenty20 international against Pakistan.

This is in view of the heavy workload Brendon will shoulder in the upcoming Test and (one-day) series. We believe the extra rest will be of benefit in the longer term.

McCullum sustained the back injury during New Zealand's tour of India in November.