Arizona Wildcats forward Keanu Pinder (25) tries to grab the rebound over USC Trojans forward Chimezie Metu (4) and USC Trojans forward Nick Rakocevic (31) in the first half during a game at the Galen Center on Thursday, Jan. 19, 2017. Mamta Popat / Arizona Daily Star

LOS ANGELES – Lauri Markkenen had 23 points, including a critical late 3-pointer, to help the Arizona Wildcats hold off a second-half USC rally and beat the Trojans 73-66 at the Galen Center on Thursday.

Arizona held leads of up to 23 points in the second half, but USC cut it to within three points in the final minutes while shooting over 50 percent in the second half. 

The Wildcats led just 67-64 entering the final minute, though Markkanen hit 3-pointer late in the shot clock with 37 seconds left to expand UA's lead to 70-64 and the Wildcats hung on from there.

While Arizona held a 22-point lead as late as with 11:01 left, 56-34, the Trojans gradually the lead down in large part because of Stewart’s hot shooting and open looks.

Stewart was only 2 of 7 from the field and made just 1 of 4 3-pointers in the first half, but hit four three-pointers in the middle of the second half to help USC cut the Wildcats’ lead into single digits.

Stewart later made a three-point play with 3:40 left to cut it to 64-57, and after Rawle Alkins fouled De'Anthony Melton behind the 3-point line with 2:36 left, Melton hit all three ensuing free throws to make it 65-60. Shaqquan Aaron later made two free throws to cut it to 67-64.

After leading 29-19 at halftime, Arizona kept jumping on the Trojans early in the second half. USC shot just 1 of 4 and had four turnovers through the first four minutes after halftime, when UA took a 42-21 lead.

The Wildcats expanded their lead up to 23 points in the rest of the half before the Trojans made it a game in the final 10 minutes.

Arizona’s defense held USC to just 25.8-percent shooting in the first half. During the first 20 minutes, Markkanen had eight points and four rebounds, while Ristic had six rebounds to lead the Wildcats, who shot 46.2 percent from the field. Point guard Parker Jackson-Cartwright struggled, however, going 0 for 4 from the field with two turnovers to his two assists.

Defensively, UA kept USC without a single 3-pointer until Elijah Stewart hit one with 1:04 left. USC missed its first eight long-range shots and was 1 for 10 for the half.

Rawle Alkins hit a pair of 3-pointers early and Markkanen added another to help UA take an early 11-4 lead while establishing its defense on the other end of the court.

The Wildcats went on to lead by up to nine points before halftime.

UA played its 19th game with guard Allonzo Trier because of his ongoing NCAA suspension for a positive PED test.

Trier said in a statement on Wednesday that he won't be able to play until a test shows that the substance is completely out of his system, and that he didn't know when that might be.

Trier's statement said he unknowingly was administered a banned substance after suffering an offseason injury, and he was tested before the season.

Sportswriter for the Arizona Daily Star covering Arizona Wildcats basketball