Scans have indicated the Spain international suffered only a small adductor tear playing for his country in Sunday's World Cup final.
The club are now hopeful the 26-year-old could be back in action in around three weeks, in time for their opening league fixture against Arsenal on August 15.
The club's head of sports science and medicine Peter Brukner told the club's website: "The initial assessment was he had a mild adductor tear and the Spanish medial staff didn't consider it to be too serious at the time.
"He had an MRI scan yesterday which confirmed a small tear. He should be able to resume training within two to three weeks and be able to play again within three to four weeks."
Torres suffered the injury late in extra-time of Spain's glorious triumph against Holland in Johannesburg, soon after coming on as a substitute.
News that Torres, 26, will miss the pre-season campaign is a blow to new manager Roy Hodgson, particularly with a Europa League qualifier to play this month, but he will be pleased his absence is not longer.
Torres was hampered by injuries last season, having a spell out with a groin problem and then having two knee operations.
He was still the club's top goalscorer with 22 but lacked match sharpness throughout the World Cup and endured a disappointing tournament on a personal level.
On the bright side for Liverpool, his problems at least appear to have dampened speculation over his future.
Torres has been regularly linked with a big-money move away from Anfield with Barcelona, Manchester City and Chelsea all suggested as potential destinations.
The player's gesture in celebrating World Cup success by wearing a Liverpool scarf has also been well received at the club.
Torres was one of four Liverpool players in the World Cup final squads along with Spanish team-mate Jose Reina and Holland pair Dirk Kuyt and Ryan Babel.
Manager Roy Hodgson said: "I think it's safe to say the pictures of Fernando in the dressing room with the World Cup certainly went down well with our fans but the club can be proud of all the players who went away to the World Cup.
"To have four players reach the final is an incredible achievement and I look forward to working with them when they return to Melwood after their holidays."
Hodgson today travelled to a pre-season training camp in Switzerland with the players who have already returned from their summer breaks.