The Brazil international missed last weekend’s victory at West Ham United after sustaining a knock against Southampton on May 7.
Firmino hasn’t been involved in team training at Melwood this week, though Klopp is hopeful of being able to call on his services for the must-win encounter with Boro.
He told journalists in his pre-match press conference: “[It’s] very positive.
“We could not decide until now, but he feels good and he feels comfortable. He did a lot of things, but was not part of team training. That’s not a problem after this long season.
“I think we will make a final test tomorrow. In this moment, I would rather say ‘yes’ than ‘perhaps’, but I am not sure.”
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