Three early fouls for the Dons gave the Cougars six quick points, putting them up 57-47 in the first minute of second half play.
Tim Derksen's 3-pointer brought the Dons within seven, but Nick Emery hit a 3 from the left corner and Chase Fischer added a breakaway layup to give the Cougars a 62-50 lead with 15:57 to play.
San Francisco's 3-point play brought them within nine, but Fischer's 3-pointer with 15 minutes to play gave them a 12-point advantage again. The two teams traded baskets for the next four minutes, until the Dons scored two straight layups to cut BYU's lead to nine with 11:21 to play. Derksen hit a 3-pointer from the right side to bring San Francisco within six, but Jordan Chatman's 3-pointer took the Cougars' lead to 75-66 with 9:30 to play.
Zac Seljaas' 3-pointer put the Cougars up 78-68 with 8:30 to play in the game. San Francisco responded with two straight layups to bring the lead within six, but a Kyle Davis layup and a Fischer 3-pointer gave BYU an 83-74 advantage with 6:45 to play.
Seljaas hit another 3 to put BYU up by 10 with six minutes to play. The Dons hung with the Cougars for the next two minutes, but Emery's 3-pointer from the left corner put the Cougars up 93-80 with four minutes to play. A combination of strong defense and offense for the next four minutes allowed them to close the game out 102-92.
Fischer led all scorers with 25 points and Seljaas ended the night with 20 points and five rebounds from the bench. Emery had 21 points and five rebounds and Kyle Collinsworth had 13 points, seven assists and four rebounds. Davis also added 14 points and nine rebounds to BYU's winning efforts.