Josip Brekalo proved to be the catalyst for the win, coming off the bench in the second half to tee up Wout Weghorst for the only goal of the game as Oliver Glasner's side continued their unbeaten start to the season. VfL now have a two-week break before travelling to RB Leipzig for their next Bundesliga outing on 19 October.
Three changes for the Wolves
Glasner made three alterations to the side that started in the UEFA Europa League against AS Saint-Étienne on Thursday. Admir Mehmedi and Joao Victor came into attack for Felix Klaus and Brekalo, who were both on the bench, while Renato Steffen replaced Jerome Roussillon, who joined John Brooks, Koen Casteels, Daniel Ginczek, Xaver Schlager and Lukas Nmecha on the absentee list.
Green-Whites on top
VfL began with the confidence a team yet to taste defeat this term and immediately went on the front foot, Mehmedi firing just over the bar inside the first couple of minutes. The next chance was not long in coming as Maximilian Arnold's clever through-ball found Weghorst, who was denied by a smart save from Union goalkeeper Rafal Gikiewicz. Glasner's men continued to push forward as they dominated the half and there were further opportunities for Robin Knoche, William and Joao Victor, who all missed the target with headers.
At the other end of the pitch, Pavao Pervan was rarely called into action and was never seriously troubled in the first 45 minutes, although the Wolves did have to remain alert. Sheraldo Becker lashed a shot into the stands from a tight angle in what was arguably the visitors' best chance, while Robert Andrich curled a free-kick wide, leaving the game scoreless at the interval.
Weghorst with the breakthrough
The Wolves maintained their pressure early in the second period and were awarded a penalty in the 52nd minute after Weghorst was wrestled to the ground inside the Union box, but referee Bastian Dankert reversed his initial decision after a VAR consultation revealed a handball in the build-up. Undeterred, VfL continued to turn the screw and deservedly took the lead when Brekalo – who had only been on the pitch for three minutes – jinked his way past a defender on the edge of the Union box before sliding a pass through to Weghorst, who rifled in his fourth league goal of the season.
The Green-Whites refused to rest on their laurels, though, and went close to scoring a second a number of times, most notably when Arnold's audacious effort direct from a corner had Gikiewicz scrambling to save it on the line. Klaus skewed a shot wide as the final whistle approached but in the end it mattered little as the Wolves' impressive start to the campaign continued.
VfL Wolfsburg: Pervan – Knoche, Bruma, Tisserand – William, Guilavogui (c), Arnold, Steffen (Gerhardt 90+2') – Mehmedi (Brekalo 67'), Victor (Klaus 83') – Weghorst
Union Berlin: Gikiewicz – Trimmel (c), Friedrich, Subotic (Mees 86'), Schlotterbeck, Lenz – Becker (Ingvartsen 72'), Gentner (Ujah 77'), Andrich, Bülter – Andersson
Goals: 1-0 Weghorst (69')
Yellow cards: Guilavogui, Bruma / Andrich, Friedrich
Referee: Bastian Dankert (Rostock)