Doubts have been raised over whether Watson would be ready for the first Ashes Test due to the problem, but Lehmann remains confident over the all-rounder's fitness.
"The reports from our medical team on Shane's recovery from injury are pleasing," Lehmann told reporters.
"He is making good progress and responding well to treatment. If that continues, we have confidence that he will be fit for the first Test.
"We won't be taking any chances with his preparation, though, and he will miss next week's Shield match between New South Wales and Queensland at Allan Border Field."
The first Test begins on November 21.