Brandon Ashley led the way with a career high-tying 21 points, Kaleb Tarczewski added 14 with eight rebounds and T.J. McConnell dished out 11 assists without a turnover as Arizona (27-3, 15-2 Pac-12) kept itself in the hunt for a possible No. 1 regional seed in the NCAA Tournament.
The Wildcats had already secured the top seed in the upcoming Pac-12 Tournament with Saturday's 63-57 win at No. 13 Utah that completed a season sweep of the second-place Utes.
Arizona shot 56.7 percent from the floor, held the Golden Bears to a 38.1 percent field goal rate and opened up a 21-point lead at halftime in impressively rolling to a 13th victory in 14 games.
Tyrone Wallace paced Cal (17-13, 7-10) with 16 points in the lopsided loss, the Golden Bears' fourth defeat in its last five outings. Sam Singer finished with 13 and Christian Behrens pulled down 10 rebounds.
Moore, who saw extended playing time because of Chicago's recent slew of injuries, scored 13 of his career-high 19 points in the fourth quarter, including the deciding 3-pointer with 2.1 seconds remaining.
Fellow reserve Nikola Mirotic poured in 14 of his 26 points in the final frame, while Paul Gasol and Mike Dunleavy each chipped in with 21 points for the Bulls, who won for the third time in four games despite trailing by as many as 16.
Westbrook came into the game riding a string of four consecutive triple- doubles, the longest stretch the NBA has seen since Michael Jordan had seven in a row from March 25-April 6, 1989. The All-Star guard recorded a franchise- record third straight 40-point performance with 43 points but shot just 2-of-9 in the fourth quarter and turned the ball over after Moore's go-ahead 3. He also fell shy of a triple-double by two rebounds and three assists.
Serge Ibaka added 25 points and nine rebounds for Oklahoma City, which was coming off a hard-fought 123-118 overtime win over the 76ers on Wednesday.
Whether the win over the Sixers took away their legs down the stretch is up for debate, but the Thunder went over four minutes without scoring in crunch time. The Bulls scored eight straight during the drought to pull within 100-99, and it was still a one-point game, 105-104, inside the final minute.
After Westbrook airballed a shot from the top of the key, Chicago called timeout with 4.9 seconds left and drew up an inbounds play that saw Gasol take an entry pass on the block and throw a touch pass to Moore in the corner. Moore, even though Westbrook was charging at him, calmly drilled the dagger.
Westbrook accidentally stepped out of bounds on the ensuing inbounds, and the Bulls held on from there.
Ibaka got going early with buckets on Oklahoma City's first two possessions and ended his 11-point opening quarter with two more jumpers in the final minute, staking the Thunder to a 30-18 lead.
The Bulls went down by 16 before pounding the ball inside and scoring 18 of their 30 second-quarter points in the paint. Gasol's buzzer-beating tip in pulled the hosts within two, 50-48, at halftime.
Westbrook erupted for 19 points on 8-of-11 shooting in the third, which ended with the Thunder holding a 79-72 advantage.
Westbrook shot 14-of-32 overall ... Gasol pulled down 12 rebounds, while Joakim Noah totaled four points, 12 boards and nine assists for the Bulls, who won the battle in the paint 54-30 ... The Thunder fell to 5-3 during Kevin Durant's latest injury ... Chicago went 5-2 on its homestand ... Craig Sager, TNT's colorful sideline reporter, worked his first game since beginning treatments for leukemia last year.