Wayne Rooney, who led D.C. United’s second-half charge from last place to a playoff berth, was fourth at 7.8 percent and Los Angeles FC’s Carlos Vela received 5.3.
The next three were the New York Red Bulls' Bradley Wright-Phillips, D.C.'s Luciano Acosta and Montreal’s Ignacio Piatti.
Martinez, 25, bested the previous scoring mark of 27 with two months left in the regular season and finished with 31 in 34 matches. Roy Lassiter (1996), Chris Wondolowski (2012) and Wright-Phillips (2014) had shared the record.
Martinez notched three hat tricks and, between May 30 and Aug. 24, scored in 13 of 14 games, including nine in a row. He contributed 44 percent of Atlanta’s MLS-best 70 goals, converted 55 percent of his shots on goal and added six assists.
In the playoffs, Martinez has three goals in four outings as Atlanta has advanced to MLS Cup this Saturday against the Portland Timbers at sold-out Mercedes-Benz Stadium.
In two MLS seasons, Martinez has scored 50 goals in 54 regular season appearances (51 starts).
He is the first Venezuelan to win the honor and the eighth South American. Last year’s recipient was Portland’s Diego Valeri, an Argentine attacker.
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