The 37-year-old, who played 27 tests and 117 one-day internationals, was diagnosed with the condition during a routine check-up with his state team.
''It has been identified early and Darren will undergo blood-thinning treatment for the next three months,'' SACA physiotherapist John Porter told Australian Associated Press.
''We are very confident that this will not delay his recovery from the Achilles operation and that he will be fit to play with the Redbacks when the season starts in October.'' Lehmann stepped down as South Australia captain at the end of last season but plans to play on as a middle-order batsman and slow left-arm bowler.
REUTERS KK PM0725