SYDNEY'S No.22 draft pick Jesse Dattoli will be sidelined for at least four months after suffering a lumbar stress reaction in his lower back.

In a major blow to his first pre-season at the Swans, the 18-year-old will be unable to run for six weeks as he recovers from the injury.

"Jesse reported some low-grade back pain earlier this week and scans have revealed he has developed a stress injury in his lower back," head of physiotherapy and medical services Damian Raper said.

"He will have a break over Christmas before commencing off legs strength and conditioning work in the New Year."

Dattoli, a small forward/midfielder in the mould of Hawthorn's Dylan Moore, joined the Swans from the Northern Knights after averaging 23 disposals, four clearances and 1.7 goals per game in 2024.

He was also part of Victoria Metro's title-winning team at the Marsh Under-18 National Championships, kicking three goals in his four matches.

The Swans will take on Gold Coast at People First Stadium in the AAMI Community Series on Friday, February 27, before meeting Hawthorn in Opening Round at the SCG on Friday, March 7.