The England international has been heavily linked with a move to Premier League giant Manchester United, although Dortmund does not appear to be keen on parting with its most prized asset.
Sancho got BVB on its way at the Schauinsland-Reisen-Arena with a 14th-minute penalty before Jude Bellingham, an off-season signing from Birmingham City, marked his debut with a goal after half an hour.
Jude Bellingham, the youngest goalscorer in the 110 year history of Borussia Dortmund ⭐️ pic.twitter.com/SFLBowNAz1— Borussia Dortmund (@BlackYellow) September 14, 2020
Any hopes the host had of clawing its way back into the game were dashed shortly before the interval when Dominic Volkmer was dismissed for a professional foul on Erling Haaland, Thorgan Hazard added a third from the resulting free-kick.
Giovanni Reyna and Marco Reus then added gloss to the scoreline in the second half as Dortmund warmed up for its Bundesliga opener against Borussia Monchengladbach on Sunday (AEST) in style.