NZ's premier opener reveals how he tackles self-doubt.

You wouldn't have thought, watching Martin Guptill lay waste to one of the best bowling attacks in world cricket in that recent, startling knock of 180 against South Africa, but New Zealand's premier opening batsman in ODIs has doubts.

Lots of doubts.

In the first of a series brought to you by BMW, Guptill reveals the self-doubt that resides in many of our top sportspeople - and particularly in cricket. The man who, in one-day internationals, seems to change gear smoothly and quickly, with some devastating driving and pulling, admits to some stutters and having to deal with "inner demons".

He talks about his close association with Martin Crowe and how love of the game gets him back into gear after he's been "kicked in the teeth".