KANSAS CITY, Mo. — Top-seeded Houston will return to the Big 12 Championship final for the second straight year, looking for its first title, while squaring off against conference newcomer and third-seeded Arizona on Saturday.But Houston coach Kelvin Sampson said the conference champion already has been determined.”The game tomorrow night doesn’t determine the Big 12 champion,” he said after his Cougars manhandled fourth-seeded BYU 74-54 in the first semifinal Friday night. “The regular season determines the Big 12 champion. That’s why you play 20 games. We played a game on December 30, and we played the last one on March 8.”This little (tournament), three games in three days? It’s an awesome chance for the Big 12 to show how great this conference is.”No. 2-ranked Houston (29-4) won the regular season with a 19-1 conference record, claiming the league title by four games over second-place Texas Tech and five games over Arizona and BYU. Houston beat Arizona 62-58 on Feb. 15 in the teams’ only other meeting this season.Houston was dominant against BYU. Emanuel Sharp scored 26 points and LJ Cryer added 20. Houston raced to a 41-20 advantage at halftime and saw the lead drop to 13 with 13:26 remaining before back-to-back 3-pointers by Sharp ended BYU’s hopes.Houston held BYU to almost 28 points below its season average. That’s to be expected from Houston, which has the No. 1 scoring defense in the country.”Our defense is our defense,” Sampson said. “We’ve been doing this for a long time.”Caleb Love scored 27 points, 17 of those in the first half, as Arizona (22-11) knocked off No. 2 seed Texas Tech 86-80 in the second semifinal.”It wasn’t easy,” Arizona coach Tommy Lloyd said. “They were tough. They fought us every step of the way. They did a really good job of putting pressure on us and getting to the free-throw line, and then they were great on the offensive glass.