River, held 1-1 at modest Olimpo, are two points behind leaders Gimnasia who beat relegated former South American champions Argentinos Juniors 2-0 at the Diego Armando Maradona stadium on Saturday.
Colombian winger Carlos Carbonero put River ahead after a quarter of an hour with his fifth goal of the Final championship with Pablo Luguercio equalising on the stroke of halftime.
River have won only once in eight away matches this year – their 2-1 victory over Boca in the ‘Superclasico’ at La Bombonera on March 30.
They were top equal with Gimnasia going into the 16th round of matches after making their Monumental stadium impregnable on a run of six home wins in a row without conceding a goal.
Boca, on the other hand, had been struggling for form, playing poorly even in victory and had fallen out of contention. They are ninth, seven points behind Gimnasia, who are chasing their first ever title.
Boca enjoyed a party atmosphere at La Bombonera against Arsenal, now coached by one of their most popular former players and holder of their all-time scoring record, Martin Palermo, who was given a resounding welcome by the home fans.
The biggest show of support, though, was for Boca captain Juan Roman Riquelme, whose inspirational performance had fans chanting: “Riquelme is not going”.
Boca president Daniel Angelici has cast doubt in recent days on whether Boca would renew the 35-year-old, injury-prone Riquelme’s contract at the end of the season next month.
Riquelme has replied on the pitch with a superb last-minute goal in last weekend’s 1-0 win at Tigre and the penalty that put Boca 2-1 up against Arsenal in first-half added time on Sunday.
“A performance like this gives you signs of hope. We won playing well which is important,” Boca coach Carlos Bianchi told reporters.
Palermo was naturally upset with the setback.
“Conceding an early goal at Boca’s ground is not easy, we managed to level it, the first half was even but it was a blow to go to the dressing room with another goal (against at halftime),” Palermo said.
“Roman had room to control the game, we were unable to counter Boca and we suffered.”
Argentinos Juniors, the club that discovered the talents of a stream of top Argentine players including Maradona and Riquelme, were relegated as Olimpo picked up a point against River.
Winners of South America’s Libertadores Cup in 1985 and Argentine champions for the third time in 2010, Argentinos are in the bottom three of the separate relegation table based on teams’ average points over three seasons and with no chance now of avoiding the drop.
(Editing by Amlan Chakraborty)