Images from Wednesday's Champions League play
Chelsea, Barcelona and Arsenal in action
FC Basel's players huddle together before their Champions League Group E soccer match against Steaua Bucharest at St. Jakob-Park in Basel November 6, 2013.RUBEN SPRICH/Reuters
Zenit's Axel Witsel, top, is challenged by Porto's Danilo during the Champions League group G soccer match between Zenit and Porto at Petrovsky stadium in St.Petersburg, Russia, on Wednesday, Nov. 6, 2013.Ivan Sekretarev/The Associated Press
Porto's Fernando, left, and Zenit's Tomas Hubocan battle for the ball during the Champions League group G soccer match between Zenit and Porto at Petrovsky stadium in St.Petersburg, Russia, on Wednesday, Nov. 6, 2013.Ivan Sekretarev/The Associated Press
Porto's Silvestre Varela, top jumps over a challenge by Zenit's Cristian Ansaldi during the Champions League group G soccer match between Zenit and Porto at Petrovsky stadium in St.Petersburg, Russia, on Wednesday, Nov. 6, 2013.Ivan Sekretarev/The Associated Press
Zenit St Petersburg's Oleg Shatov (bottom) lies on the pitch as Porto's Alex Sandro jumps above during their Champions League soccer match at the Petrovsky stadium in St. Petersburg November 6, 2013.ALEXANDER DEMIANCHUK/Reuters
Zenit St Petersburg's Nicolas Lombaerts (top) goes for a header with Porto's Danilo during their Champions League soccer match at the Petrovsky stadium in St. Petersburg November 6, 2013.ALEXANDER DEMIANCHUK/Reuters
Borussia Dortmund's Robert Lewandowski and Arsenal's Mikel Arteta, left, jump for a header during their Champions League Group F soccer match in Dortmund November 6, 2013.INA FASSBENDER/Reuters
Barcelona's Alexis Sanchez, centre, and AC Milan's Philippe Mexes challenge for the ball as Barcelona's Dani Alves looks on during their Champions League soccer match at Nou Camp stadium in Barcelona Novenber 6, 2013.GUSTAU NACARINO/Reuters
Zenit St Petersburg's Hulk (bottom) reacts as Porto's goalkeeper Helton helps him to stand up during their Champions League soccer match at the Petrovsky stadium in St. Petersburg November 6, 2013.ALEXANDER DEMIANCHUK/Reuters
FC Basel's Taulant Xhaka challenges Steaua Bucharest's Daniel Georgievski during their Champions League Group E soccer match at St. Jakob-Park in Basel November 6, 2013.ARND WIEGMANN/Reuters
Barcelona's Alexis Sanchez faces AC Milan's Philippe Mexes, right, during the Champions League group H soccer match between FC Barcelona and AC Milan, at the Camp Nou stadium, in Barcelona, Spain, Wednesday, Nov. 6, 2013.Manu Fernandez/The Associated Press
Borussia Dortmund's Jakub Blaszczykowski and Arsenal's Bacary Sagna jump for a header during their Champions League Group F soccer match in Dortmund November 6, 2013.WOLFGANG RATTAY/Reuters
Barcelona's Lionel Messi, left, scores a penalty past AC Milan's goalkeeper Christian Abbiati during their Champions League soccer match at Nou Camp stadium in Barcelona Novenber 6, 2013.GUSTAU NACARINO/Reuters
Arsenal's Mesut Oezil reacts during the Champions League Group F soccer match against Borussia Dortmund, in Dortmund November 6, 2013.INA FASSBENDER/Reuters
Arsenal's Mikel Arteta, left, is shown a yellow card by referee Bjorn Kuipers during the Champions League Group F soccer match against Borussia Dortmund, in Dortmund November 6, 2013.WOLFGANG RATTAY/Reuters
Chelsea's Samuel Eto'o celebrates with teammates after scoring a goal against FC Schalke 04 during their Champions League soccer match at Stamford Bridge in London November 6, 2013.EDDIE KEOGH/Reuters
Celtic's Charlie Mulgrew, left, and Ajax Amsterdam's Davy Klaassen fight for the ball during their Champions League soccer match at Amsterdam Arena November 6, 2013.TOUSSAINT KLUITERS/Reuters
Ajax Amsterdam's Siem de Jong reacts during a Champions League soccer match against Celtic at Amsterdam Arena November 6, 2013.TOUSSAINT KLUITERS/Reuters
Ajax Amsterdam's Lasse Schone celebrates his goal against Celtic during their Champions League soccer match at Amsterdam Arena November 6, 2013.MICHAEL KOOREN/Reuters
Atletico Madrid's Raul Garcia, right, scores his goal as he jumps with Austria Vienna's Christian Ramsebner, left, during a Champions League Group G soccer match between Atletico Madrid and Austria Vienna, at the Vicente Calderon stadium in Madrid, Wednesday, Nov. 6, 2013.Andres Kudacki/The Associated Press
Ajax's Nicolai Boilesen, right, and Celtic's Emilio Izaguirre, rear, vie for the ball during the Champions League Group H soccer match between Ajax Amsterdam and Celtic Glasgow at ArenA stadium in Amsterdam, Netherlands, Wednesday, Nov. 6, 2013.Peter Dejong/The Associated Press
FC Basel's Fabian Schaer jumps for a header with Steaua Bucharest's Federico Piovaccari (R) during their Champions League Group E soccer match at St. Jakob-Park in Basel November 6, 2013.ARND WIEGMANN/Reuters
Napoli's Gokhan Inler, right, celebrates after scoring against Olympique Marseille during their Champions League soccer match at San Paolo stadium in Naples November 6, 2013.CIRO DE LUCA/Reuters