The one positive for King and the Saints is that it's a calf muscle problem, rather than the repeated knee injuries that meant he played no football last year.
But off-contract Port Adelaide ruck Ivan Soldo will not play this year after rupturing the ACL in his right knee during training.
St Kilda confirmed on Monday that King suffered a "low-grade" calf injury as he returned to full training.
That will delay the comeback of one of the AFL's most injury-cursed players by two to three weeks.
"Max has put together a solid block of work this pre-season and it is disappointing for him to face this setback albeit on the lower end of the scale," new Saints football boss Lenny Hayes said on the club website.
"However, we remain optimistic and will do everything we can to support Max and have him back in full training as soon as possible."
Injuries meant the 2018 No.4 draft pick managed only 23 games across the 2023-24 seasons. His last AFL game was round 17 in the 2024 campaign.
King needed more surgery on his right knee in December, sidelining him until late last month. He initially injured the knee in a February practice match and had two other operations.
The Saints re-signed King to a six-year deal in 2024, taking him to 2032.
Since his 2020 senior debut, King has kicked 159 goals in 83 games.
Also on Monday, Port Adelaide confirmed back-up ruck Soldo suffered the dreaded ACL injury in a training drill earlier in the day.
It is a massive blow for the 29-year-old, who has played only eight games since joining the Power from Richmond ahead of the 2024 season.
Soldo was part of the 2019 premiership-winning team at the Tigers before rupturing the ACL in his left knee in 2020.
He moved to Alberton on a three-year contract in 2024, but fell behind Jordon Sweet as the Power's first-choice ruck, featuring in just one game last year.
Elsewhere, Collingwood star Nick Daicos had strapping on his left leg at training, while rising Adelaide star Sid Draper's day was reportedly cut short with a recurring groin issue.
Daicos is one of the biggest Victorian names for Saturday night's State of Origin match against WA at Perth's Optus Stadium.
Coleman Medallist Jeremy Cameron pulled out of the Victorian line-up on Sunday as he continues to recover from the broken arm he suffered in last year's grand final loss to Brisbane.
Cameron told the Geelong website that "ideally" with another week of contact work he might be ready for the game.
Gold Coast key forward Ben King, last season's Coleman Medal runner-up, has taken Cameron's place for Victoria.
19°C