The Liverpool captain is in hospital after contracting an infection in the groin injury which caused him to miss the final 10 weeks of last season.
Blow: Steven Gerrard (left) will be out of action until September
Gerrard, 31, will sit out England's Wembley friendly against Holland andLiverpool's first three Premier League matches.
His availability for the Euro 2012 qualifying matches against Bulgaria and Wales in early September is also in serious doubt.
Out: Gerrard's last appearance came against Manchester United in March
Liverpool said in a statement: 'Steven Gerrard today began a course ofantibiotic treatment for an infection related to an ongoing groin problem.
'He is expected to remain in hospital for several days while the precautionary procedure is completed.
'The player will then return to Melwood to continue his rehabilitation programme and is expected to be available for selection in September.'
Gerrard has been dogged by groin problems for years and seems to be paying for playing through the pain barrier against Manchester United on March 6.
He had an injection before the game, which was seen as crucial if Liverpool were to help stop United winning arecord 19th English title.
Chance: Alberto Aquilani may be required at Liverpool following Gerrard's injury
Liverpool won 3-1, but United went on to be champions and Gerrard hasnot played since. His team appeared to thrive in his absence, putting together a good run under returning manager Kenny Dalglish.
But they have endured a difficult pre-season, letting in 12 goals in four warm-up matches.
Gerrard's absence will put pressure on midfield signings Jordan Henderson and Charlie Adam as the club seek to avoid a repeat of their appalling start to last season.
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