Their worst fear happened two days later instead.
Duncan is out indefinitely after spraining his left ankle in a 111-96 win over the Golden State Warriors on Monday night, dealing the NBA's winningest team its first significant injury all season and at nearly the worst possible time.
Spurs coach Gregg Popovich said Duncan would be out "a while" but had no timetable. Spurs forward Antonio McDyess said he spoke with Duncan after the game and thinks the 34-year-old All-Star will miss at least a couple of weeks.
"I thought he had done real damage, like broken or fractured," McDyess said. "I was just happy to see it was just a severe sprain. I actually thought it was worse."
Manu Ginobili scored 28 points, and Tony Parker had 17 points and 15 assists. Parker was among the first to rush over to Duncan after he crashed to the court barely four minutes into the game. Parker then turned and winced toward Popovich, who stood with his hands in his pockets, watching his two-time MVP lay on his side and clutch his left foot with both hands.
"It's not flowers and lollipops," Popovich said about what he was thinking at the time.
Ekpe Udoh led Golden State with 15 points. It was Udoh's foot that Duncan appeared to be trying to avoid while landing awkwardly after hitting a short jumper in the first quarter.
X-rays on Duncan's foot were negative.
Troubled by aches and injuries the previous two seasons, Duncan's surprising durability until now has been a big reason why the Spurs (57-13) have led the NBA all season and are on pace to surpass their franchise record of 63 wins set in 2005-06.
The Spurs have a seven-game lead over the Los Angeles Lakers in the West with 12 games left. That breathing room afforded Popovich the luxury Saturday of giving Duncan his first game off all season, after Duncan had been the only Spurs player to start the first 68 games.
Duncan had played 32 minutes the night before in Dallas. Popovich said he didn't want to risk an injury.
He's got a big one now.
"I saw him in pain. He's not one of those guys that's going to pretend or do that if he is not hurting," Ginobili said. "It's bad, but hopefully it's just a couple of games and he'll be back soon."
Acie Law and Dorell Wright scored 14 apiece as the Warriors dropped their fifth straight. Golden State played a night after getting pummeled at Dallas by 28 points, and have one stop left in Houston on Wednesday before returning home Friday to host Toronto.
"You don't want to see a good guy like that getting hurt," Golden State coach Keith Smart said of Duncan.
Rookie Tiago Splitter, the 7-footer who got his first NBA start in place of Duncan on Saturday, filled in again for his idol and finished with 10 points and 14 rebounds.
Steve Novak scored 13 points, and Jefferson had 12 for the Spurs.
The loss assured Golden State a 14th straight season without a win in San Antonio. Put another way, the Warriors have never won in San Antonio since Duncan was drafted in 1997.
But Golden State has given the Spurs two Duncan scares this season.
In January, Duncan fell to the floor and cringed for about a minute during a 113-102 win at Golden State. He was diagnosed with a hyperextended left knee and returned to the game.
That wasn't the case this time. He limped off the court with the help of trainers and did not return. McDyess said Duncan was icing the ankle at halftime and described the injury to him as painful.
Earlier this month, the Spurs announced that Parker would likely miss two to four weeks with a sprained calf muscle. He wound up missing just one game.
Parker tied a season high in assists. ... Spurs F DeJuan Blair didn't play after spraining his left wrist in Saturday's win over the Bobcats. Blair is expected to return Wednesday.