Adams limped off the floor after Arizona's final shot attempt and went to get X-rays after the game.
"We'll see how it is," UCLA coach Ben Howland said.
Ditching their new pajama-like uniforms for the more traditional white with blue and yellow trim, the Bruins (25-8) fought back from an 11-point second-half deficit after pulling off a similar rally against Arizona State in the quarterfinals. Adams triggered it, scoring 17 points in the final 9:57, including 15 straight during one stretch.
Kyle Anderson put UCLA in front on a putback with 22 seconds left and Arizona's Solomon Hill missed a midrange jumper, sending the Bruins into Saturday night's title game.
"The leaders on our team stressed to the five guys that are out there that we have to stay calm, being down 11 or 9 or whatever it was," said Anderson, who had 10 points. "I think that's what we did a really good job of, and we were able to fight back for a second time and end up with the win."
Arizona (25-7) was effective in slowing down Shabazz Muhammad and Larry Drew II, but had no answer for Adams once he got going in the second half.
Muhammad finished with 11 points on 4-of-11 shooting after a quiet first half and Drew went scoreless after missing all five of his shots.
Adams made up for it, hitting 6 of 13 shots and 11 of 13 from the free-throw line for the Pac-12 regular-season champs in an entertaining game at the MGM Grand Garden Arena.