Franco Di Santo claimed a 17-minute hat trick Thursday as Schalke beat Asteras Tripoli 4-0 in the Europa League, while Borussia Dortmund, Liverpool, Tottenham, Ajax and Celtic were held to draws.
Di Santo completed his feat with a penalty before halftime and Klaas Jan Huntelaar rounded off the scoring in the 84th with his 49th goal in UEFA competitions for Schalke to take charge of Group K with seven goals scored and none conceded in two games.
Sparta Prague defeated APOEL 2-0 to stay two points behind the Gelsenkirchen-based side.
Dortmund drew 1-1 at PAOK despite dominating possession. Robert Mak put the Greek side ahead in the 34th, before Gonzalo Castro equalized in the 72nd when Jonas Hoffman's dummy deceived goalkeeper Robin Olsen. It was Dortmund's third consecutive draw after starting the season with 11 straight wins across all competitions.
Riot police intervened at the beginning of the second half when visiting fans lit flares and threw some toward the pitch and PAOK supporters. Eight German fans were arrested.
"We're not happy with how our fans presented themselves," Dortmund coach Thomas Tuchel said. "It's very annoying, it doesn't help us."
Russian side Krasnodar defeated Azerbaijani team Gabala 2-1 in the other Group C game.
Despite Adam Lallana's fourth-minute opener, Liverpool could only draw 1-1 with visiting FC Sion thanks to Ebenezer Assifuah's equalizer in the 11th. Rubin Kazan drew 0-0 with Bordeaux in the other group game.
Stephan El Shaarawy scored late for Monaco to snatch a 1-1 draw against Tottenham. Azerbaijani side Qarabag defeated Anderlecht 1-0 in the other Group J match.
Ajax was held to a 1-1 draw at Molde in Norway. Molde's 40-year-old captain Daniel Hestad became the Europa League's oldest goalscorer when he converted from close range in the eighth minute, only for Viktor Fischer to equalize 11 minutes later.
Molde leads Group A two points ahead of Celtic, which was held to a 2-2 draw at home by Fenerbahce after substitute Fernandao struck twice for the visitors.
Leo Baptistao's brilliant 54th-minute goal was enough for Spanish league leader Villarreal to defeat Viktoria Plzen 1-0 at home for its first win. Rapid Vienna leads Group E after its 1-0 win at Dinamo Minsk.
Athletic Bilbao lost 2-1 at AZ Alkmaar and Partizan Belgrade won 3-1 at Augsburg in Group L.
Giuseppe Rossi rounded off the scoring as Fiorentina won 4-0 at Belenenses to move second in Group I, where FC Basel stayed top with a 2-0 home win over Lech Poznan.
Another Italian side, Lazio, won 3-2 at home against Saint-Etienne, which ended the game with nine players. Lazio moved top of Group G with its first win, ahead of Dnipro Dnipropetrovsk on goal difference. The Ukrainian side lost 1-0 at Rosenborg.
In Group H, Lokomotiv Moscow claimed its second win from two games with a 2-0 victory over Albanian side Skenderbeu Korce, and Besiktas drew 1-1 with visiting Sporting CP.
SC Braga defeated Groningen 1-0 and Marseille was upset 1-0 at home by Liberec in Group F, while Danish side Midtjylland won 3-1 at Club Brugge and Gonzalo Higuain sealed a 2-0 win for Napoli at Legia Warsaw in Group D.