This is unfortunate news for Watson, who was activated from injured reserve last month. He originally landed on the IR due to a hamstring back in September, so it appears that it is not an aggravated injury.
Watson, 30, is a former seventh-round pick of the Buccaneers back in 2010. He wound up playing out his rookie contract with the team before signings on with the Jaguars in March of 2014.
After brief stints with the Cowboys, Patriots and Broncos, Watson signed a three-year, $6 million contract that included $1 million guaranteed with the 49ers last year. He stands to make base salaries of $1.05 million and $1.45 million over the next two year.
In 2018, Watson appeared in four games for the 49ers and recorded six total tackles, two sacks, and one forced fumble.