Taylor also knocked down two timely 3-pointers and a layup midway through the second half on the way to 13 points, while Delon Wright's two free throws with 2:11 left tied the game at 50.
Wright added another free throw with 10.1 seconds remaining and Cal star Justin Cobbs missed a 3-pointer before the final buzzer.
After Taylor's free throws at 1:46, Renan Lenz made a key block on the other end moments later to help seal it. Cobbs missed two free throws with 47 seconds left.
Krystkowiak's Utes (20-9, 9-8 Pac-12) won their third straight since a 67-63 overtime loss at home against now-No. 3 Arizona on Feb. 19 and hope a nice run at next week's Pac-12 tournament might boost their NCAA tournament hopes despite a handful of narrow defeats.
Richard Solomon had 19 points and 14 rebounds and Tyrone Wallace scored 11 for Cal (18-12, 9-8) on a night Cobbs was limited to six points on 2-for-6 shooting—well below his 15.8 scoring average.
Wallace made two free throws with 4:03 left to tie the game at 48, and he became the first player to reach double figures.
One sign neither team had its best night: On consecutive possessions, each team tossed up an airball from 3-point range in the waning moments.
Taylor found his rhythm when it mattered.
His 3-pointer with 10:51 remaining put Utah up 39-36, then 6-foot-9 Lenz set up his own dunk with 9:57 to go after blocking a shot on the defensive end. Taylor hit another 3 on Utah's next possession, then a driving layup with 6:10 to go.
It was a costly loss for the Golden Bears, who began the final week of regular-season play tied for fourth place in the Pac-12 with Colorado and Stanford. Colorado beat Stanford 59-56 earlier Wednesday at Maples Pavilion.
While positioning for the Pac-12 tournament and a potential bye is still to be determined, Cal certainly hurt its dwindling NCAA tournament hopes.
Cal lost for the fourth time in five games and has its first three-game losing streak of the season. The Bears host Colorado on Saturday to wrap up the conference schedule ahead of the conference tournament in Las Vegas.
Kenneth Ogbe knocked down back-to-back 3-pointers during a 9-0 run as Utah took its first lead of the game at 18-17 with 7:13 remaining in the first half.
The Bears struggled at times against Utah's pressure and committed eight first-half turnovers, with Utah scoring 10 points off those mistakes on the way to a 26-24 halftime lead.
This marked the lone regular-season meeting between the schools based on this year's schedule. Cal won both regular-season meetings last season before losing in overtime to the Utes in the Pac-12 tournament quarterfinals.
The Bears made 4 of their initial 6 shots and 6 of 11 before Utah emerged from a slow start that featured a travel, two missed free throws and a missed field goal its first three possessions. Cal went cold midway through the first half and was held to five points during a seven-minute span.