The San Antonio Spurs, plagued by injuries, have added Rudy Gay and Derrick White to the list of unavailable players, which now stands at four with less than a week until the regular-season opener.

Gay has an inflamed bursa in a heel and was not available for Friday's preseason finale against the Orlando Magic, coach Gregg Popovich said, according to the San Antonio Express News. The move was precautionary, and the Spurs will take a closer look at him when they return to San Antonio.

White, meanwhile, has a plantar fascia tear in his left foot, further depleting the team's depth at guard. Popovich initially told reporters that White could miss six to eight weeks, but then later said it could just be two to four weeks.

A source told ESPN that White will know for sure the amount of time he's expected to miss by early next week.

White's injury, which happened during Wednesday's preseason game against the Atlanta Hawks, was discovered after he underwent an MRI on Thursday night in San Antonio. An official timeline for his return will be determined at a later date.

This sets the Spurs back a total of three guards. Dejounte Murray tore his right ACL on Sunday in a preseason loss to the Houston Rockets and is out for the season. Rookie Lonnie Walker IV underwent surgery the following day to repair a torn right meniscus and is expected to be out of action for six to eight weeks.

Following the departures of Kawhi Leonard (trade), Manu Ginobili (retirement) and Tony Parker (free agency), Murray was expected to lead a revamped Spurs roster that also features LaMarcus Aldridge and DeMar DeRozan, who was acquired in the Leonard trade.

After Murray's injury, White was the starting point guard in the Spurs' loss to Atlanta on Wednesday, when he had 15 points, 6 rebounds and 3 assists in 29 minutes.

Third-year man Bryn Forbes, who scored 22 points off the bench against the Hawks, will start Friday against the Magic. Veteran backup Patty Mills, the longest-tenured Spurs player on the roster, will remain with the second unit.

The Spurs open the regular season against the Minnesota Timberwolves on Wednesday.