BUENOS AIRES, Argentina (AP) — Argentina's River Plate defeated Mexico's Tigres 3-0 on Wednesday to win an unlikely third Copa Libertadores title—and the club's first in nearly 20 years.

Striker Lucas Alario scored with a header in the 45th minute and midfielder Carlos Sanchez added to the lead by converting a penalty kick in the 75th.

Defender Ramiro Funes Mori then sealed the victory under pouring rain off a corner kick in the 79th, giving the storied club an unlikely title after a difficult start to the Latin American competition.

River Plate had the worst campaign among the 16 teams that advanced to the knockout stage, only managing to make it that far with some help from Tigres, which beat Peruvian club Juan Aurich in the final round of group stage matches to help River secure its spot.

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River Plate then reached the quarterfinals after rival Boca Juniors was eliminated from the tournament because its fans sprayed players with an eye irritant believed to be either pepper spray or mace in the teams' second-leg match at Boca's La Bombonera Stadium.

River Plate had won the first leg 1-0 at home and the return game was scoreless when it was interrupted at halftime.

River had to overcome more difficulties in the semis. The club lost the first leg 1-0 at home to two-time defending Brazilian champion Cruzeiro, before rebounding with a stunning 3-0 win in Brazil.

With the title, River Plate secured a place in FIFA's Club World Cup in Japan in December.

River and Tigres drew 0-0 in the first leg of the final in Mexico last week.

River Plate previously won the tournament in 1986 and 1996. This year's triumph comes only four years after it was relegated to the Argentine second division for the first time, marking one of the worst periods in the club's history.

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