Villarreal 1-0 Bayern Munich: Arnaut Danjuma scored the only goal of the game before both teams spurn chances to add to the first-leg scoreline
Former Bournemouth winger Danjuma gave the Spaniards a slender advantage going into the return leg by scoring the only goal early in the first half at Estadio de la Ceramica.
But it could have been worse for Bayern, who produced a disappointing display, as Villarreal had another effort ruled out for offside before they struck a post through Gerard Moreno.
The home side, backed by a vociferous crowd, made an excellent start and took an eighth-minute lead through Danjuma.
On-loan Tottenham midfielder Giovani Lo Celso cut the ball back into the area before Danjuma diverted Daniel Parejo’s shot into the bottom corner.
Spain defender Raul Albiol’s well-timed challenge on the edge of the box denied Serge Gnabry a scoring chance as Bayern looked to get a foothold in the game.
But the German champions were relieved to see Pau Torres fail to connect with a flick-on from Parejo’s free-kick as Villarreal threatened again.
And the stadium erupted just before the break when the Spaniards thought they had taken a deserved two-goal lead.
Francis Coquelin’s attempted cross flew into the net, but referee Anthony Taylor was told the French midfielder had been offside after a VAR check and Bayern breathed again.
The visitors, who had failed to register a shot on target, had it all to do at half-time.
Thomas Muller was inches away from diverting in a cross for an equaliser early in the second period, but there was no respite for Bayern, who were spared by the woodwork when Moreno’s shot hit a post in the 53rd minute.
Bayern sent on Leroy Sane and Leon Goretzka for Gnabry and Muller and in the 66th minute Alphonso Davies fired straight at Villarreal goalkeeper Geronimo Rulli. It was Bayern’s first effort on target.
The Bundesliga side pressed in the final 15 minutes, but still found chances hard to come by and Alfonso Pedraza fired a golden chance wide for Villarreal in the 87th minute.