Rivard made four 3-pointers en route to 17 points while Chambers added 16 with five assists for the Crimson (19-9, 11-3 Ivy), who clinched a share of the championship with victory.
They then waited for the outcome of Princeton's game against Brown, which ended in a 80-67 Brown win. The result handed the Crimson the outright league title and its automatic NCAA berth.
Wesley Saunders added 14 points for Harvard, which went 9-of 15 from long range en route to its third straight Ivy League crown.
Miles Asafo-Adjei led the Big Red (13-18, 5-9) with 15 points and four assists.
Errick Peck (14, eight rebounds) and Nolan Cressler (12, nine) also reached double figures for Cornell.