MILWAUKEE (WTAQ) - Milwaukee Brewers’ first baseman Corey Hart will miss the first six weeks of the regular season after his previously-injured right knee acted up again.

Hart noticed swelling during an off-season workout – and an MRI confirmed a defect in the joint surface of the knee.

He’ll need surgery, which team doctor William Raasch will perform next Tuesday. Hart is expected to be out for 3 to 4 months.

Brewers’ officials say Hart is not sure about an incident that caused the knee to swell. The Brewers expect Mat Gamel to play at first while Hart is out.

Also Friday, the Brewers reached one-year contract agreements with all three of their remaining players who were eligible for salary arbitration.

Closer John Axford got almost a 10-fold increase in his salary, from $525,000 last year to $5 million this season. Axford helped the Brewers get to within two victories of a World Series in 2011. He struggled at times a year ago, but still managed to get 35 saves.