As the NBA season slowly approaches, a handful of marquee players remain uncertain to be active by the start of the season on October. Derrick Rose is a guarantee to return after sitting out the year while rehabbing a torn ACL, but the same might not be true for stars like Rajon Rondo and Russell Westbrook. Both athletes are coming back from knee injuries as well and have no timetable for when their return will take place.

While speaking on 98.5 SportsHub, Boston Celtics president Danny Ainge noted that he would be shocked if Rondo was healthy by the team's Oct. 30 opener. While the All-Star point guard has been rehabbing aggressively, the team would rather take it slow with their top player instead of rushing him back on the court.

"We've just seen examples of why we shouldn't give dates of expected return," said Ainge. "We'll just take it week by week and he'll continue to get evaluated, but he's working extremely hard, and he wants to play. He's excited for the new team. I think there was a time when all of [Boston's offeseason moves were] happening that he was sort of wondering, 'Where do I fit in here?' What's our team?' But I think Rajon is in a very good place right now."

Ainge predicts a more realistic return date for Rondo would be around December. Paul Pierce echoed those beliefs months ago, noting that Rondo will be expected to step up as the leader and he needs to be fully healthy when he returns to take over the team.

Westbrook is another player not giving any sort of timetable of when fans can expect him back. The Oklahoma City Thunder star is confident he will be better than ever when he returns, but he is not ready to say exactly when that is.

"I tried taking it one day at a time and not [worry about] the timetable," Westbrook said, via The Oklahoman. "Just take it one day at a time and try to find a way to strengthen myself and make sure I'm ready to go when it's time."

Thunder general manager Sam Presti remains hopeful that Westerbrook can participate in training camp on a limited basis. The team's training camp starts Saturday and the point guard will be there to continue rehab. Westbrook told the newspaper that he spent most of the summer strengthening his legs and working with therapists to get as healthy as possible in quick amount of time.