Carlos Tevez scored for the first time since his return to Boca Juniors last month but his team could only manage a 1-1 draw with nine-man San Lorenzo.
Tevez, 34 on Monday, struck with a header after a Leonardo Jara cross, cancelling out Ruben Botta's long-range effort at the Nuevo Gasometro stadium, reports Xinhua news agency.
Midfielder Facundo Quignon was sent off just before halftime when he earned his second yellow card for a rash challenge.
The hosts were reduced to nine men with eight minutes left when full-back Gabriel Rojas was also booked for a second time for a crude tackle.
The result maintained Boca's six-point lead over San Lorenzo in the Superliga Argentina standings, with both teams having played 14 matches.
Tevez, who began his career at Boca in 2001, had spells with Corinthians, West Ham, Manchester United, Manchester City and Juventus before rejoining the Buenos Aires outfit in 2015.
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After a disappointing 2017 season with China's Shanghai Shenhua, Tevez began his third spell with Boca last month.
--IANS
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