Arizona's injury situation got worse Wednesday night.

Starting point guard Parker Jackson-Cartwright suffered a high right ankle sprain in the first half of an 85-63 victory over Texas Southern in Tucson, Ariz., as the 16th-ranked Wildcats are now down to seven available scholarship players.

"From what I understand, he is going to be out for a considerable amount of time," Arizona coach Sean Miller said of Jackson-Cartwright. "It's just the way it is."

Freshman forward Lauri Markkanen scored 19 points to lead 16th-ranked Arizona (6-1) over Texas Southern (4-3) in a game in which the Wildcats were never threatened. Markkanen, who scored 11 points in the first nine minutes to fuel Arizona's fast start, made 5 of 6 3-point attempts. He added six rebounds and five assists with no turnovers.

Jackson-Cartwright left the game with 12:27 to go in the first half, gimpy and favoring his right leg as he walked to the sideline. He had appeared to suffer the injury a couple of possessions earlier on a play in which he hit the floor. He left the court to receive treatment and did not return to the sideline during the game.

Because of injuries and other attrition, including the ongoing unexplained absence of starting guard Allonzo Trier, Arizona has been playing with just eight scholarship players.

The Wildcats started the summer with 12 eligible scholarship players but lost touted incoming freshman guard Terrance Ferguson (turned pro), graduate transfer guard Talbott Denny to a season-ending knee injury and redshirt freshman forward Ray Smith to his third torn ACL.

Texas Southern forward Derrick Griffin had 12 points and 11 rebounds for his third double-double of the season. Guard Zach Lofton led the Tigers in scoring with 19 points.

Four other Arizona players posted double-figure points: guard Kobi Simmons (15), wing Rawle Alkins (14), guard Kadeem Allen (14) and center Dusan Ristic (10).

Allen added six rebounds and seven assists, moving over from shooting guard to the point, which he played most of last season.

"I'm comfortable there," Allen said. "I'm just out there playing basketball."

Allen already plays all three perimeter positions but will have to be the lead point guard. Simmons will get backup minutes there. Markkanen, who can play either post position, will have to play small forward on a team that has three scholarship guards/wings.

"Kadeem has always been asked to do a lot," Miller said of the team's only available senior. "Doing whatever it takes to win is really what he's done. He's playing with his heart."

Asked who will now be the eighth man in the rotation, Miller said, "I don't know."

Arizona started quickly, hitting nine of its first 12 shots while taking a 19-4 lead. The Wildcats led by double digits the rest of the half, making another surge after the Tigers closed within 29-18.

Arizona went on a 14-2 run that included back-to-back alley-oop dunks from the combination of Simmons and Allen, each assisting on the other's slam. The Wildcats shot 57.1 percent from the field in the first half (20 of 35), using superior size against the man-to-man defense of Texas Southern, which didn't switch to zone until late in the half.

"We got overwhelmed early," Tigers coach Mike Davis said. "It's not about us winning or losing games early, but we didn't want to get down like we got down. We got down because we didn't shelter the basketball, we shot the ball too quickly and we turned it over."

The Wildcats led 45-26 at halftime and the lead never dipped below 13 in the second half.

NOTES: Arizona was without G Allonzo Trier for the seventh consecutive game amid rumored eligibility issues. The school has not commented on the nature of the absence or a timetable for a potential return. ... The Wildcats added freshman walk-on G Kory Jones to the roster. He helped guide Westfield High in Chantilly, Va., to the 2016 Virginia 6A state championship. Sean Miller said he might add another walk-on, given the new injury to Parker Jackson-Cartwright. ... Texas Southern is in the midst of 16 consecutive non-conference road games to start the season.