Both of the La Liga representatives in the Europa League from the Basque country went down to defeats in the 6pm kick offs.
Real Sociedad faced Zenit in Russia with both sides having picked up heavy wins in their opening games. Zenit took the lead after just 5 minutes when a misplaced pass from Ruben Pardo found Emiliano Rigoni who fired past Geronimo Rulli from 20 yards.
La Real were dominating possession but found themselves 2-0 down after 24 minutes after another horror mistake in defence. This time it was Rulli to blame as he came racing out of his box only to misjudge the flight of the ball allowing Aleksandr Kokorin to move on to the ball and slot into the empty net.
They pulled one back just before half time when Diego Llorente nodded home his third goal in the two games to give La Real a lifeline.
They continued to press Zenit, who had also earlier hit the bar, but they were undone on the hour mark when Branislav Ivanovic’s cross was bulleted home by Kokorin to make it 3-1.
Rosenborg defeated Vardar Skopje by the same scoreline in the group’s other match.
Next up for Sociedad is a double header against Vardar Skopje with the first game taking place in Macedonia on the 19th of October.
Athletic Club also suffered a defeat in their match, a shock 1-0 loss to Ukrainians Zorya Luhansk at the San Mames.
A goal from a corner by Igor Kharatin separated the sides in a fantastic victory for the visitors giving them their first 3 points of the campaign and leaving Athletic still looking for their first goal of the tournament.
Iker Muniain was stretchered off late on for Bilbao after taking a bang to the knee leaving him in agony. The extent of his injury however remains unknown but Athletic will hope it is not too serious with Muniain arguably their best player on the night and so far this season.
Athletic will face Swedes Oestersunds, who beat Hertha Berlin by a goal to nil, in their next two games with the group now wide open as the two favourites sit on 1 point each having drawn with each other in Germany on Matchday 1.
In the second set of games Villarreal travelled to Israel to face Maccabi Tel Aviv.
The Yellow Submarine, playing in their away scarlet coloured strip, were disappointing in a rather drab game that ended 0-0.
Samu Castillejo came the closest for the La Liga side when his shot came back off the post.
The result sees Villarreal remain top of the group level on points with Slavia Prague who drew 1-1 with Astana earlier on. Those 2 meet in Spain next time out in the first game of the double header.