A below-par Liverpool were held to a goalless draw by Fulham at Anfield, a result which maintains their unbeaten start to the season but will surely be viewed as a missed opportunity.The visitors had lost their opening three Premier League games and have looked vulnerable defensively under former Liverpool right-back Alvaro Arbeloa, but Andoni Iraola’s side could not take advantage.There was a full league debut for Bradley Barcola but he had a quiet afternoon as the home side failed to follow up their Champions League victory against Atletico Madrid with another win.Were Liverpool suffering a European hangover?Andoni Iraola is juggling league and Champions League commitments for the first time (Matt McNulty/Getty Images)Iraola enjoyed his first experience of coaching in the Champions League in midweek, but he would not have been pleased with how the demand of three games in a week seemed to impact his players.Iraola admitted when he arrived at Liverpool that working out how to get his team to play the high-intensity style he wants three times a week was something he was going to have to learn. Not since his first managerial job, in 2018 at AEK Larnaca (he led them to the Europa League group stage) has he had to balance the demands of domestic and European football — and this is at a much higher standard.After an initial bright opening when Alexander Isak flashed a shot past the post after being put through by Barcola, Liverpool were sluggish. In possession they repeatedly misplaced routine passes and lacked dynamism. Off the ball they did not have the same intensity that was evident in the victory over Atletico.Iraola did make changes to his starting XI, bringing in Kostas Tsimikas, Ryan Gravenberch and Victor Munoz for Milos Kerkez, Alexis Mac Allister and Rio Ngumoha. All three featured from the bench on Wednesday, but with the exception of a couple of bright moments from Munoz, they did not particularly look fresher than their team-mates. It was telling that the three players who were brought into the team were the first three players taken off by Iraola.