Boca Juniors were crowned champions of Argentina for a 32nd time after rivals Banfield suffered defeat on Tuesday.
A 1-0 loss to San Lorenzo left Banfield unable to catch Boca, who are five points clear at the top.
Guillermo Barros Schelotto's men have lost just three league games this season, with Boca's title moving them a step closer to River Plate's record of 36.
Boca have been led by Dario Benedetto (18 league goals, three assists) and 21-year-old Argentinian Cristian Pavon (nine goals, seven assists).
Carlos Tevez had netted five goals before his lucrative move to Shanghai Shenhua in December.
Fernando Belluschi scored a 56th-minute winner for San Lorenzo in their victory over Banfield.
Boca (59 points) have two games to play, as do third-placed River (52), while Banfield (54) and San Lorenzo (52) have one each.