David Kravish had 11 points and 11 rebounds for the Bears, who had five players score in double figures.
Crabbe, who scored a career-high 33 against Pepperdine on Tuesday, had 17 points in the second half and helped key a decisive run to keep the Bears undefeated on the young season.
Brett Olson had 17 and leading scorer Chris Udofia had 16 points for the Pioneers. Sophomore Royce O’Neale heated up late to finish with 14 points for Denver.
Cal (3-0) led by one at the break but quickly opened up a seven-point lead behind the scoring of Cobbs and Robert Thurman. Thurman scored six quick points as the Bears went ahead 45-39 near the 12-minute mark.
Udofia, who had just 2 points on 1 for 6 shooting in the first half, kept the Pioneers close. He hit his first five shots of the second and converted a three point play with 11:39 left to pull Denver to within 45-42.
Cal stepped up after that. Cobbs hit a runner in the lane, Crabbe drained a 3-pointer and Thurman hit a short baseline hook to push the Bears’ advantage to 52-42 with 8:27 left.
After a layup by Blake Foeman stopped the run, the Bears scored eight straight points to open up a 60-44 lead with 5:01 left.
Denver pulled within 69-61 on a 3-pointer by Olson and seven straight points from O’Neale, but Cal hit its free throws down the stretch to keep Denver at bay.
Udofia, who had carried the Pioneers to start the second, missed three shots in the face of amped up defense by Cal. Denver missed seven shots overall and committed two turnovers as Cal took control.
The Pioneers (1-2) scored the first eight points of the game before Cal got going. The Bears trailed by five when they went on a 13-3 run to take a 19-14 lead midway through the first half.
Denver scored the next six points, but Cal opened up a 29-24 lead late in the first before the Pioneers pulled to 29-28 at intermission.
Olson led Denver with 8 points in the first half, while Kravish and Cobbs had 7 each for the Bears.