Argentine side River, who beat arch-rivals Boca Juniors to win the Copa Libertadores this month but suffered a humiliating defeat by Al Ain in a penalty shootout in the semi-finals, took the lead midway through the first half with a header from midfielder Bruno Zuculini.
Gonzalo "Pity" Martinez signed off from a memorable career with the Argentine club, including two Copa Libertadores triumphs, by scoring twice in the second half after coming off the bench in his last appearance before heading to MLS side Atlanta United.
Martinez increased River's lead in the 73rd minute and completed the thrashing with a chipped finish in stoppage time after Colombian striker Rafael Santos Borre had scored the third goal from the penalty spot.
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