Chris Cairns acknowledges cheers after reaching his half century against Bangladesh in Chittagong on Tuesday. Cairns scored 74. (AFP)

Chittagong: Fast bowler Kyle Mills grabbed four wickets in a dream spell as New Zealand thrashed Bangladesh by 138 runs in the opening one-day International on Tuesday.

Mills, 25, virtually reduced the match to a no-contest when he wrecked the hosts top order with four quick wickets in his incisive six-over opening spell to eventually finish with a career-best haul of four for 14.

Bangladesh had an opportunity to post a rare victory against a Test-playing nation when they restricted New Zealand to a modest 224 on a slow pitch, despite a fighting 74 from man-of-the-match Chris Cairns.

But the hosts could never recover from Mills?s early blows, crashing to their fourth-lowest total of 86 to suffer their 89th defeat in 96 matches. They have so far registered just two wins against Test-playing sides ? Pakistan and Zimbabwe.

Skipper Habibul Bashar, returning to the side after missing the two-Test series against the visitors due to a thumb injury, top-scored with 22 in a dismal batting performance.

?It was a disappointing batting performance,? said Bashar. ?Our bowlers did well to restrict them, but we could not bat well. We lost too many early wickets. We hope to do better in the remaining two matches.?

New Zealand also found the runs hard to come by after electing to bat as Cairns alone defied the hosts? spin attack to help his team reach a competitive total. The tourists were struggling against some disciplined spin bowling before Cairns propped up the innings with an 83-ball 74. He hit fives sixes in his 23rd half-century.

Cairns fell in the last over when he bottom-edged a Nazmul Hossain delivery on to his stumps to become the young fast bowler?s fourth victim of the innings. Hossain, 17 ? playing in only his third one-dayer ? was the most successful bowler, finishing with four for 40 off 8.2 overs.

?The pitch was pretty tough for batting,? said New Zealand captain Daniel Vettori, who took three wickets with his left-arm spin.

?We were lucky to reach 224 as Styris and Cairns were involved in a valuable stand. We hope the wicket will be better in the next game.?

Left-arm spinners Manjural Islam Rana and Mohammed Rafique played key roles in restricting New Zealand with their tight bowling. They never allowed the top-order to score freely, conceding just 63 runs off 20 overs.