Riquelme assists steer Boca towards title
Tigre, who are challenging for the title and fighting relegation at the same time, drew at 1-1 Atletico Rafaela and troubled San Lorenzo boosted their survival hopes by coming from two goals behind to beat Newell's Old Boys 3-2.
Riquelme set Boca on their way when he floated over a free-kick which defender Juan Insaurralde met with a near post header to open the scoring after 13 minutes.
Three minutes before half-time, the mercurial playmaker got away from his marker at the far post, collected Clemente Rodriguez's long cross and laid the ball into the path of Dario Cvitanich to score into an empty net.
Pablo Mouche completed the scoring from another Riquelme pass late in the game despite the suspicion of offside.
Defending champions Boca have 32 points from 16 games with three to play in the Clausura championship, the second league tournament of the complex Argentine season.
Tigre have 29 points after Mariano Echevarria gave them a 1-1 draw at Atletico Rafaela, where Alexis Castro opened the scoring just after half-time.
However, Tigre dropped to 19th in the relegation standings, which are decided over three seasons, putting them back in the danger zone.
San Lorenzo, meanwhile, climbed to 18th, putting them in the play-off zone, with their spectacular win over Newell's Old Boys, who dropped four points behind Boca in the Clausura.
Newell's raced to a 2-0 lead in half an hour as Pablo Perez scored with a long-range effort and Fabian Munoz pounced after the hosts gave the ball away in defence.
San Lorenzo, considered one of the big five Buenos Aires clubs, were level within nine minutes of the restart as Emmanuel Gigliotti headed in a corner and Uruguayan Carlos Bueno rifled in the equaliser.
The hosts missed a flurry of chances before Gigliotti struck again with a diving header three minutes from time.