Bayern Munich have over the years lost their dominance on the European soil though have been enjoying authoritative rule domestically.
And to regain their lost European status, the Allianz Arena outfit are focused on rebuilding their squad following the departures of Arjen Robben and Franck Ribery, as Sane has been considered as the right option to fill the void left by the veterans.
However, Bayern’s attempt to sign the left-footed winger has become a complex task due to Manchester City’s reluctance in offloading the player.
But Lewandowski believes the club should not only channel their focus on the transfer deal of Leroy Sane, urging the side to also consider augmenting other departments in the squad.
"I think we need three new players," Lewandowski told Sport Bild.
"Even if Sane comes, we need another winger. Maybe also a number six or attacking midfielder.
"We lost three players in attack with Franck Ribery, Arjen Robben and James and so far we have not made a new signing there."
With Bayern’s bid previously rejected by the Citizens, the German champions will look to improve their new offer to be able to secure the signature of Sane in the coming days.
Scoring 22 goals in thirty-three Bundesliga games with seven assists, Lewandowski helped Bayern retain the title last season.
After losing the German Super Cup to Borussia Dortmund, Bayern will begin their new Bundesliga season with a game against Hertha Berlin on August 16 at the Allianz Arena.