The German coach celebrated his first competitive match at the helm with three points as Barca came from behind against Ruben Baraja's solid Valencia side.
The Polish forward suffered the injury in Monday's win in a friendly against Turkey.
The champions' victory denies leaders Real Madrid the chance to take the crown by simply beating Cadiz next Saturday. Los Blancos are 11 points clear of Barcelona with five matches remaining.
Lewandowski set up goals for Joao Felix and Fermin Lopez either side of striking himself to pull Barcelona second, eight points behind leaders Real Madrid.
Barcelona came flying out of the blocks with goals from Fermin Lopez and Joao Cancelo but after Amir Rrahmani pulled one back, the Catalans started to sweat.
Robert Lewandowski's brace snatched champions Barcelona a 2-1 win over lowly Celta Vigo to leave them third in La Liga, trailing leaders Real Madrid by seven points.
Bayern Munich striker Harry Kane said Robert Lewandowski's league goals record was "still a bit too far away" despite again scoring a brace in a 4-2 win over Heidenheim on Saturday.
Barcelona striker Robert Lewandowski wants Lionel Messi back in the club this summer as the Argentine superstar’s contract with PSG is set to expire in June.
Barcelona face Madrid at the Santiago Bernabeu on Thursday in the first leg of the cup tie, already without injured duo Pedri and Ousmane Dembele
The German coach celebrated his first competitive match at the helm with three points as Barca came from behind against Ruben Baraja's solid Valencia side.
The Polish forward suffered the injury in Monday's win in a friendly against Turkey.
The champions' victory denies leaders Real Madrid the chance to take the crown by simply beating Cadiz next Saturday. Los Blancos are 11 points clear of Barcelona with five matches remaining.
Lewandowski set up goals for Joao Felix and Fermin Lopez either side of striking himself to pull Barcelona second, eight points behind leaders Real Madrid.
Barcelona came flying out of the blocks with goals from Fermin Lopez and Joao Cancelo but after Amir Rrahmani pulled one back, the Catalans started to sweat.
Robert Lewandowski's brace snatched champions Barcelona a 2-1 win over lowly Celta Vigo to leave them third in La Liga, trailing leaders Real Madrid by seven points.
Bayern Munich striker Harry Kane said Robert Lewandowski's league goals record was "still a bit too far away" despite again scoring a brace in a 4-2 win over Heidenheim on Saturday.
Barcelona striker Robert Lewandowski wants Lionel Messi back in the club this summer as the Argentine superstar’s contract with PSG is set to expire in June.
Barcelona face Madrid at the Santiago Bernabeu on Thursday in the first leg of the cup tie, already without injured duo Pedri and Ousmane Dembele
Raphinha and Robert Lewandowski's strikes helped Barcelona move eight points clear at the top of La Liga with a 2-1 win at Real Betis on Wednesday.