The Spurs likely are to begin their first road swing of the season without All-Star forward Tim Duncan.

The 37-year-old big man left Wednesday's season opener 70 seconds into the second half after taking an inadvertent elbow from Memphis' Tony Allen.

A CT scan performed Thursday by Spurs doctors revealed a chest contusion. He is doubtful for Friday's game at the Los Angeles Lakers, which kicks off a three-game road trip.

Duncan experienced spasms in his shoulder and neck before leaving the 101-94 victory over the Grizzlies, coach Gregg Popovich said.

“Nerves, man, it's a crazy thing,” guard Danny Green said. “You can get hit in the pinky and your ankle might be gone. You never know how it's going to go.”

Duncan, who scored three points and was 1 of 6 before exiting, is considered day-to-day. After leaving Los Angeles, the Spurs play Saturday at Portland and Tuesday at Denver.

“He's a big key to what we do, especially defensively,” Green said. “He's great at rebounding and blocking or altering shots. I have a lot of faith in our guys, but Timmy's tough. I think he'll be back soon.”

Healthy start for Leonard: After a season in which he missed 24 games with left quadriceps tendinitis and a summer in which he was ordered to stay off the basketball court, small forward Kawhi Leonard declared himself 100 percent healthy for the start of the 2013-14 season.

Then he proved it in a strong opening-night performance against the Grizzlies.