"We are very proud of our team," said head coach Paul Thomas. "We got out of the gate strong and did a wonderful job of keeping the lead. Each game is a new experience... we learned from our loss on Friday and did something positive."
Saint Mary's is now 1-1 on the year, while Oregon drops its season opener.
Danielle Mauldin poured in a career-high 20 points, along with a career-high tying 16 rebounds. Ashlee Smith came off the bench to score 14 points in 23 minutes.
Jackie Nared added 12 points, seven rebounds and a career-high seven assists. Morgan Hatten and Kate Gaze scored 10 points apiece. Carli Rosenthal scored all nine of her points in the first-half. Hatten also added 13 rebounds.
Oregon was led by Danielle Love with 13 points as the Ducks stayed in the game with the three-pointer, connecting on 13 in the game.
Saint Mary's outrebounded Oregon 56-42 and the Gaels made 19-of-23 free-throws, while the Ducks went 4-for-6 from the line. Oregon kept the game close by connecting on 13-of-45 from behind the arc, while the Gaels hit 5-of-17 three-pointers.
Saint Mary's opened up its largest lead of the first half just before halftime, leading 41-30 after Rosenthal scored in the paint. Oregon scored before half to make the score 41-32 SMC at the break.
In the second-half, the Gaels opened up their largest lead of the game at 59-47 with 12:23 remaining. The Ducks pulled within three points on a couple of occasions, the last time at 65-62 with 6:26 remaining. Saint Mary's then went on a key 10-2 run to take a 75-64 lead after a Gaze basket with 3:19 remaining.
Oregon could do no better than match baskets down the stretch as the Gaels iced the game with free-throws.
Saint Mary's is back in action on Thursday night when it takes on California in Berkeley at 7:00 p.m.