Mairaj's feat gave India its first skeet medal at a World Cup.
The 40-year-old Indian shooter finished with an overall tally of 14 in the gold medal match but lost out to Marcus Svensson of Sweden in a shoot off after the latter was also tied at 14. Tamarro Casandro of Italy won the bronze.
Mairaj shot 122 in the qualifying, 15/16 in semi-final stage of six-men final round and then 14+1 in the gold medal match.
Mairaj's best international performance previous to this was a team gold in the Commonwealth Shooting Championship in 2010.
Out of 26 World Cup appearances this was his best ever finish in his first-ever final round.
Earlier in the year, he became India's first ever skeet shooter to win an Olympic quota place.
Mairaj qualified for his maiden Olympics in September last year at the ISSF Shotgun World Cup that was held in Lonato in Italy, finishing in sixth place and thereby becoming the first Indian to qualify in the skeet event at the Olympics.
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