Joe Rahon had 10 assists for Saint Mary's (2-0), which assisted on 24 of the team's 30 made baskets. The Gaels shot 58 percent from the field and 42 percent from beyond the 3-point arc. Stefan Gonzalez made 4-of-5 three-point attempts and scored 13 points.
Manhattan's offense struggled in the second half of its season opener, scoring 7 points in the first 9:46 as Saint Mary's grew its lead to 27 points.
The Jaspers shot 38 percent from the field and made 24 of 35 free throws.
Shane Richards had 23 points for Manhattan, the senior's eighth career 20-point game. Richards made 3-of-4 3-pointers. Last year he set school records for 3s in a season (92) and career (234).