After bowling Zimbabwe out for 160 inside 37 overs, Sri Lanka surrendered early wickets cheaply before Tharanga and Mendis chased down a target of 161 with more than 12 overs to spare.
Sri Lanka's top order were punished for a series of loose strokes as they sunk to 42 for three in reply to Zimbabwe's modest total, with left-arm seamer Brian Vitori picking up all three wickets.
But Mendis and Tharanga took a more circumspect approach, patiently adding 75 for the fourth wicket to make the result a formality.
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Mendis fell for 57 with Sri Lanka requiring another 44 runs for victory, but captain Tharanga finished unbeaten on 57 to see his side across the line, before lifting the trophy from a series that also involved the West Indies.
Tharanga, meanwhile, was ecstatic with the win. "I think it's a really happy moment," he said. "Full credit to the guys, they have done a really great job over the last two weeks. We knew we had to only get one good partnership. Mendis batted very well, and from there, it got easier and easier."
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His Zimbabwean counterpart Graeme Cremer was left disappointed at his side's inability to put up a strong target. "To get to a final is always nice, but we are a bit disappointed today," he said. "We didn't think our day would end like this. It was a bit difficult to bat this morning and we lost quite a few wickets together."
He, however, is confident his team will bounce back from the setback. "The team spirit is up," said Cremer. "The guys are hungry to perform and hungry to succeed and we can't ask for anything more from them."
Published in The Express Tribune, November 28th, 2016.
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