Aldridge landed awkwardly after defending Rajon Rondo's driving layup with 7:17 remaining in the quarter. He tried to play through the pain before leaving the game at the 3:02 mark of the quarter with Spurs head athletic trainer Will Sevening to head to the locker room.
Aldridge re-entered the contest with 7:39 left in the first half, before leaving to the locker room again with 3:17 remaining until intermission.
The Spurs announced at halftime that Aldridge had an ankle sprain and would not return to action. The Spurs did not offer an update on Aldridge following Wednesday's 121-116 loss.
Teammate Rudy Gay was optimistic Aldridge will be OK.
"Yeah, I think he'll be fine. I'm hoping he'll be fine," Gay said of Aldridge after the game. "We obviously need our big dog. He's a soldier, he'll play."
For an already shorthanded team missing Leonard, the latest setback with Aldridge could prove crushing.
The club had already held out veteran guard Manu Ginobili (bruised sternum) from Sunday's rodeo road trip finale at the? Cleveland Cavaliers, and Aldridge missed two games of that trip to return to San Antonio to receive routine treatment on a chronically sore right knee. Guard Danny Green missed a game on Friday at the? Denver Nuggets?after coming down with food poisoning from room service spaghetti, while Gay had just made his return in Denver after missing the previous 23 games due to heel bursitis.
Veteran center? Pau Gasol also contributed to the club's injury woes, sitting out Wednesday's matchup due to a bone bruise in his left knee that Spurs coach Gregg Popovich said would likely take more than a week to heal.
In all, Spurs players have now missed 149 games this season due to injuries (169 total).
A clear timetable for Leonard's return remains unclear.
"Of course, there's a protocol," Popovich said in regard to Leonard's status before Wednesday's game. "He's doing what he's supposed to do. He's working hard at it. He wants to be back. When and if he feels like he's ready to go, he'll be there."