Smoltz remained at the team's complex in Kissimmee while the Braves played the Cleveland Indians.
"Probably tomorrow, for sure," Smoltz told The Associated Press when asked Monday morning about his plans to throw.
Smoltz missed his scheduled start Friday because of tightness in the shoulder.
Smoltz and manager Bobby Cox say they don't believe the discomfort is a serious concern. Smoltz said Friday he would have pitched with the tightness in a regular-season game.
Cox said he has talked with Smoltz and other starters about the possibility the right-hander could open the season on the disabled list.
Tim Hudson will be the starting pitcher when the Braves open Sunday at Washington. The team plays only one game in Washington before returning to Atlanta.
Smoltz had been projected to start Monday's home opener against Pittsburgh, but the Braves have an off day the following day and won't need a fifth starter until April 6 -- the last game of a three-game series against the New York Mets. Smoltz could be activated for the April 6 game.
Cox said Smoltz might pitch in a minor league game later this week. Jeff Bennett is scheduled to start for the Braves in Wednesday's game against Washington, the day Smoltz would have pitched.
Smoltz said he is confident the discomfort will go away with rest. He said he had a similar knot in the same area last season.
Smoltz has made only one spring start. He allowed five runs -- three earned -- in 4 w innings in an 11-10 loss to the Tampa Bay Rays on March 15. He opened the start with four scoreless innings.
Cox appeared to come close to announcing rookie right-hander Jair Jurrjens as the team's fifth starter on Monday. When asked if he preferred to have a right-hander in the rotation between left-handers Tom Glavine and Mike Hampton, Cox said he could move up Jurrjens to pitch between the two.