On 19 September 1961, Peñarol won their first Intercontinental Cup, beating Benfica in a replay at the Estadio Centenario. They went on to win the competition twice more to become its most successful team.
The Uruguayans had participated in the inaugural Intercontinental Cup the year before, but lost to Real Madrid over two legs. In 1961, they returned to the cup to face Benfica, but lost the first leg 1-0 in Lisbon on 4 September. Thirteen days later, they hosted the Portuguese side at Montevideo and won convincingly by the score of 5-0. Under the rules at the time, the cup was decided on points and not goal differential, so they went to a replay to determine the winner.
Meeting again the Estadio Centenario, Peñarol took a quick lead with a 5th-minute goal from inside forward José Sasía. Half an hour later, Benfica forward Eusébio, who was then in his second season with the club and had not played in the first two matches, found a 35th-minute equalizer. But just five minutes after that, Sasía converted a penalty to restore the lead for Peñarol and they held on to claim the 2-1 victory.
They went on to win it again in 1966 and 1982 to become the first team to win the Intercontinental Cup three times. Their tally has since been matched by four other clubs--Nacional, AC Milan, Real Madrid, and Boca Juniors--but has never been exceeded.