Hart was actually in the middle of a rehab assignment following offseason surgery on his right knee when he began feeling the discomfort in the healthier knee. It's believed he may have overcompensated during his recovery, which in turn caused the wear and tear and will ultimately result in the operation.
Though the Brewers are not contenders in the National League Central this season — they currently sit alone in last place — this is still a big blow for them. With the trade deadline approaching, a healthy Hart (assuming the right knee held up) was likely to draw a significant amount of interest from teams looking to add right-handed pop at first base, corner outfield and even designated hitter. He would have been a particularly interesting option for the Yankees in the wake of Mark Teixeira's season-ending wrist surgery.
Instead, the Brewers will end up eating his $10 million salary this season without getting any production or a decent prospect or two to show for it.
As for Hart, it'll hurt him in the pocketbook as well. As he enters free agency and his age 32 season, he'll be coming off surgery on both knees. That will be a tough sell for a large contract, and depending on how deep or desperate the market gets, he might have to settle on something short-term. That's a big deal as the window on securing a long-term contract starts to close for a veteran who will continue to carry the health risk tag.
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