Allonzo Trier hit the 30-point mark and Deandre Ayton posted a double-double in the second straight game, helping Arizona hold off UMBC and standout guard Darius Lyles.
Lyles led the Retrievers with 31 points on 10-for-21 shooting while UMBC kept within range much of the game, but Trier and Ayton (19 points, 13 rebounds) were too much for the America East team.
Having scored 32 points in UA’s season opener Friday against NAU, Trier became only the eighth UA player in history to have scored 30 points or more in two straight games. Only one, Jerryd Bayless in 2007-08, scored three 30-point games (against ASU, Cal and Stanford).
Up 56-47 at halftime, the Wildcats struggled early in the second half. After Jourdan Grant hit an open 3-pointer in the right corner to cut Arizona’s lead to just 58-55 with 17:48 left, UA coach Sean Miller called timeout.
Miller subbed in forward Ira Lee and guard Alex Barcello after the timeout, removing Emmanuel Akot and Dusan Ristic. UA built leads of up to 16 points over the middle of the second half, though a 3-pointer from UMBC's Brandon Horvath cut UA’s lead to 79-68 with 8:41 remaining.
But the Wildcats went on a 13-0 run from there to take control of the game, getting 3-pointers on consecutive possessions from Barcello to cap the run, which gave UA a 92-68 lead entering the final five minutes.
Barcello finished with eight points, five rebounds and six assists in just 17 minutes off the bench.
Overall, Arizona shot 60.9 percent from the field and held UMBC to 41.8 percent, while the Wildcats outrebounded the Retrievers 41-24 overall.
In the first half, Trier scored 15 points and Ayton had 11 while Arizona held on for a 56-47 halftime lead.
The Retrievers took an early six point lead and kept UA off balance throughout the half with a zone defense while Lyles scored 23 points on 7-fort-10 shooting and made all four 3-pointers he took.
UMBC shot 48 percent overall and 55 percent from 3-point range. Arizona shot 70 percent from the field but did so with 20 fast-break points and had seven turnovers
While Trier scored his 15 points on 5-for-10 shooting, Ayton had nine points and six rebounds in the half.
The Wildcats suited up three more players Sunday after going with just a seven-man rotation in their season opener on Friday against NAU: Dylan Smith returned from a three-game suspension for a violation of team rules to make his first appearance as a Wildcat, while forward Keanu Pinder returned from a one-game suspension for an unspecified NCAA violation and Brandon Randolph came back from a concussion suffered in practice on Nov. 3.
Randolph played two minutes in each half while UA dealt with him carefully after he was just cleared to play full-contact on Saturday. Pinder had four points, four rebounds, one block and two steals in 12 minutes while Smith had six points while hitting 2 of 4 3-pointers over 14 minutes.
Sunday's matchup was an add-on game in the Battle 4 Atlantis Tournament, in which Arizona will play in the Bahamas from Nov. 22-24, opening with North Carolina State.