Watson was carried from the field in the first half of England’s 24-15 loss at Twickenham on Saturday and was replaced by Mike Brown.
With five matches of the domestic season remaining, Bath sit seventh in the table, five points shy of the fourth and final play-off qualification berth.
But they will have to cope without Watson, who can play at full-back or on the wing, for their games against leaders Exeter Chiefs, fellow top-four contenders Leicester Tigers, Saracens, Gloucester and bottom club London Irish.
“Anthony has been in superb form this year, and we’re obviously really disappointed to have lost him at a critical part of the season,” said Bath director of rugby Todd Blackadder.
— England Rugby (@EnglandRugby) March 19, 2018
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