After winning the FA Cup last season, Liverpool are set to face Premier League champions Man City at the King Power Stadium on July 30 for the Community Shield.
The Reds are aiming to lift the trophy for the first time since 2006, but they will have to do it without Jota, who has been ruled out of the encounter.
The 25-year-old travelled with his team-mates to the Far East for Liverpool's pre-season tour, but he pulled up in training with a hamstring problem that affected him in last month's international games for Portugal.
As a result of the injury, Jota missed Liverpool's 2-0 friendly win over Crystal Palace, with Klopp stating that the player will not return in time for the Community Shield.
The Liverpool manager told reporters: "Diogo, unlucky eh? He had an injury from the end of last season. He trained fully yesterday but got injured again. That's really not cool.
"Now we have to wait for the results. He had an assessment this morning so we will have to see. It's in the same area."
While Jota waits to learn the extent of his injury, Liverpool will face RB Leipzig in Germany and Red Bull Salzburg in Austria before facing Man City in the Community Shield.