NZ v BAN: I Can't Describe It, It's An Unbelievable Thing: Bangladesh Captain Mominul Haque

An ecstatic Bangladesh captain Mominul Haque was lost for words at his side's shock eight-wicket win over world champions New Zealand at Mount Maunganui on Wednesday.

It is the first time Bangladesh have won in New Zealand, and Mominul could not contain his emotion when Mushfiqur Rahim clouted a boundary off Kyle Jamieson to seal the famous victory by eight wickets.

"I can't describe it. It's an unbelievable thing," Mominul, who was not out 13, said after hugging Mushfiqur and waving to the Bangladesh team and support staff.

It was not only a boost for Bangladesh cricket but it also severely dented New Zealand's hopes of retaining their world Test crown.

In one of cricket's biggest upsets, Bangladesh arrived in New Zealand on the back of a 2-0 home series loss to Pakistan and less than seven months since New Zealand had won the World Test Championship by beating India in the final in England.

New Zealand, 130 behind after the first innings, were only 17 runs in front at stumps on day four with five wickets remaining, but Mominul said he refused to contemplate victory until it happened.

"Honestly, I couldn't sleep yesterday because of the pressure and I didn't know what will happen today," he said, adding that after poor preparation for the tour, Bangladesh had deliberately not focused on winning, or on New Zealand, but on executing their own plans.

"It was very important to win the Test match, everyone knows we have to improve our Test cricket, (but) we didn't focus on the result, we focused on the process," he said.

"If you think it's going to be tough it will be tough."

After a loss and a draw away to India last month, the Black Caps had expected to sweep the two-Test series to get back in the World Championship race, particularly before South Africa arrive in February.

India, with wins away over England and South Africa, have made a strong start as have Australia who have swept the first three Ashes Tests against England, while Sri Lanka have a 2-0 series win over the West Indies.

New Zealand captain Tom Latham rejected suggestions the Black Caps may have underestimated Bangladesh.

He said his team prepared as for any Test but "they certainly outplayed us through the five days".

"We know we've got to turn up and play our brand of cricket and unfortunately we couldn't quite do that for five days here."

The second Test starts in Christchurch on Sunday.