Sané was born in Villeneuve-sur-Lot in southwestern France and began his football career playing for local club US Lormont on the outskirts of Bordeaux.

For the 2009–10 pre-season, Sané featured regularly and performed well, most notably in a 3–1 win over Spanish club Athletic Bilbao after appearing as a second-half substitute.

After spending seven senior years at Bordeaux, Sané departed the club and signed for Bundesliga side Werder Bremen for an undisclosed fee.

[2][3] In January 2018, the club's sporting director Frank Baumann announced that Sané would not be part of the team "for the time being" because he had been absent from training on two days without a valid excuse.

[5][6] He made his debut as a halftime substitute away to New York City on 17 March and scored his first goal for the club against Real Salt Lake in a 3–1 home victory on 6 May.

[10] Sané was an unused substitute in the next three league games as well as a 2–0 KNVB Cup semi-final win over Ajax before the season was canceled due to the COVID-19 pandemic in April.