He missed each of England's five outings across February and March and Saracens director of rugby Mark McCall confirmed the wait is almost over for the 23-year-old.
However, should he take on Clermont this weekend if will be from the replacements' bench, with veteran stand-off Charlie Hodgson - who toured New Zealand with the Lions in 2005 - holding onto the No.10 shirt.
"He's fit and available," said McCall. "Charlie Hodgson will start at outside-half but it will be great to have someone like Owen on the bench. He will get his start pretty soon."
Barritt returned from his own knee problem last weekend as Sarries beat Leicester Tigers and McCall is hoping for a similar showing from the 28-year-old.
"In games as big as this one, you need your warriors," he added. "No one exemplifies that more than Brad. His influence is profound."
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