The big serving Italian, who is ranked 141st in the world, spoiled Žemlja's comeback to the tournament following an illness that saw him miss much of the past two years.

Vanni served 15 aces in the match and won nearly 90% of first serve points to leave Žemlja with little chance of breaking.

Despite the loss, the finals appearance in Portorož is the first notable success for Žemlja since winning the EUR 42,500 tournament two years ago.

Žemlja had been ranked as high as 41st on the men's tour before a mystery illness caused him to lose most of the past two years. He has since been climbing the rankings from a low of 890.

In the doubles draw in Portorož, second seeded French-Indian pairing of Fabrice Martin and Purav Raja proved too strong for Alexander Bury of Belarus and Andreas Siljeström of Sweden in the final, winning 7:6 (5), 4:6, 18:16.