Liverpool manager Jurgen Klopp said it was "clear and obvious" that Dries Mertens' controversial penalty should not have been given after the holders slipped to defeat at Napoli in their Champions League opener on Tuesday. The Premier League leaders fell behind in the 82nd minute after Jose Callejon went down easily under pressure from Andy Robertson, before Fernando Llorente's stoppage-time strike secured Napoli a 2-0 win.

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Jurgen Klopp not convinced with the penalty

"I don't think it's a penalty," Klopp told BT Sport.

"What can I say, for me, it is clear and obvious, no penalty. He jumps before any contact, we can't change that." 
 

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Liverpool became the first holders to lose their opening game of the following Champions League campaign since AC Milan in 1994, as their front three of Mohamed Salah, Sadio Mane and Roberto Firmino were all guilty of wasting chances."It should hurt because there were opportunities for us," added Klopp."It was an open game with a lot of counter-attacks, but we didn't finish them off and that is a problem."We controlled moments but had not enough chances in the end. We made decisions that were not right and have to accept the result."It was very often the final ball that was not right."  Liverpool next face a difficult trip to Stamford Bridge to take on Chelsea in the Premier League on Sunday, and host Salzburg -- who thrashed Genk 6-2 on Tuesday -- in their second Champions League Group E game on October 2. 

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English hopes in Europa League

Manchester United and last year's finalists Arsenal headline an English trio that also features Europa League newcomers Wolves while record five-time champions Sevilla figure to be among the primary contenders as the group stage begins Thursday.United, Europa League winners in 2017, will host Astana in Group L as Ole Gunnar Solskjaer's side face opponents from Kazakhstan for the first time in club history. Unai Emery's Arsenal return to the competition after last season's 4-1 defeat by Chelsea in the final in Baku saw the Blues pip them to Champions League qualification. 

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