Chasing 109 to win, Hong Kong scored the winning runs with two balls to spare after losing quick wickets early in the innings.
Spinners Regmi and Gauchan took three wickets apiece as Nepal crushed Hong Kong by 80 runs in their World Twenty20 qualifier match on Sunday.
Hong Kong overcame a disastrous start to beat Papua New Guinea by 29 runs to secure a historic berth in the ICC World Twenty20 2014.
However, Ireland recovered from their loss to Namibia with an easy 10-wicket win over Kenya.
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