Angelo Stiller's pass found the Swabians' captain after some excellent movement, and Undav finished calmly in the 29th minute to make it 1-0. According to OptaUndav's goal gave him the most goal contributions by a German player in the main rounds of European competitions since last season.
Across that period, the 30-year-old has contributed to twelve goals, scoring four and assisting eight. He set up two goals in VfB's 3-1 opening win against Viking Stavanger and registered nine goal contributions last season in the Europa League, where Stuttgart reached the round of 16 before losing to FC Porto.
Undav had failed to score in all three competitions before this goal. The striker began the season with Achilles tendon problems and faced criticism for some unfortunate performances. In September, new Germany coach Jürgen Klopp also left him out of his XXL squad.
Deniz Undav impressed at the World Cup and for VfB Stuttgart
At the World Cup, Undav scored three goals in four games for Germany and was one of the few bright spots. He recorded 25 goals and 14 assists for VfB before taking over the captaincy from Atakan Karazor for the new season.
Coach Sebastian Hoeneß always stood by Undav. "Anyone who starts trying to explain Undav through statistics has already lost, in my view," he said before the Champions League opener.
VfB went on to win 3-0, making a perfect start in the Champions League. An own goal by Sandro Cruz from a Josha Vagnoman cross (65th minute) and a goal from Ermedin Demirovic (90th) completed the scoring.
VfB Stuttgart: Sebastian Hoeneß makes five changes
After the game in Paderborn (2-0), Hoeneß made five changes, including in goal: Fabian Bredlow replaced Dennis Seimen, who had recently made his Bundesliga debut after a long injury lay-off. "Dennis is coming back from a four-month injury," Hoeneß said of the change in goal.
Bredlow had little to do at first as VfB dominated. Ramon Hendriks (15th minute) and Undav (24th) missed the first chances before the captain's shot took a slight deflection on its way in for 1-0. Shortly afterwards, Josha Vagnoman struck the crossbar with a powerful shot. Dominik Takac then kept the half-time deficit from growing.
After the break, Bratislava, coached by former world-class player Yaya Toure, grew into the game. Sandro Cruz (61st minute) hit the crossbar. VfB wobbled briefly before Cruz unluckily deflected Vagnoman's driven cross into his own net. Demirovic, who had scored a hat-trick against Stavanger, headed in late on.