ShareLiverpool were beaten 1-0 by Arsenal in the Premier League, but Virgil van Dijk was adamant Alexander Isak should have had a penalty.Virgil van Dijk questioned why Alexander Isak would have to make more of a shirt tug to earn a penalty when there are "50 cameras" around the stadium to see the incident.Van Dijk's comments came in the wake of Liverpool's 1-0 defeat to Arsenal at Anfield on Sunday, with Mikel Arteta's side going three points clear at the top of the standings. Kai Havertz capitalised on Alisson Becker's sloppy pass to score in the 16th minute, but Liverpool responded well to going behind, though they were unable to find an equaliser.Liverpool's best chances came during a frantic spell in the first half, with Florian Wirtz's free-kick hitting the crossbar before Alexis Mac Allister headed over inside the box.The Reds also appealed for a penalty in the opening 45 minutes when Bradley Barcola's cross just evaded the head of Isak, with replays showing the Liverpool number nine was having his shirt pulled by Jurrien Timber, but their protests were waved away by referee Andy Madley and VAR. Isak did not make a fuss about the decision and even stayed on his feet during the incident, though Van Dijk made his feelings known once the final whistle had blown. "I think it was a clear penalty. I've seen it back, and I've seen it being given. It wasn't meant to be," Van Dijk said. "We have 50 cameras."Why does he have to complain when there are so many cameras? Everyone has seen it. In the end, it wasn't given, and we lost the game unfortunately, so well done to Arsenal."Van Dijk's frustrations were echoed by Andoni Iraola, who added: "Especially the Alex [Isak] one. Gakpo was sustained holding, I understand. The Alex one is a clear penalty. "You hold the shirt, we can all see that he holds the shirt. Because he doesn't go to the floor, you are not going to call the penalty. I don't understand it."When asked if Isak should have gone down, Iraola added: "That's the problem we have with the game. Because he doesn't dive and go to the floor."The fact that you are even asking me if he should go to the floor, if he goes to the floor, they call the penalty 100%."It should be like this, but it is what it is. Next time, the managers should tell Alex to go to the floor, otherwise they won't call it."But it was another difficult outing, particularly in front of goal for Liverpool. For the first time on record (since 2003-04), they failed to record a shot on target in a Premier League game at Anfield. It was their 442nd league match played at the venue since the start of the 2003-04 campaign.Liverpool have scored just four goals at Anfield in the Premier League this season, their joint-fewest after five home matches in a top-flight campaign (also four in 1913-14 and 2012-13), though Iraola believed his team deserved at least a goal. "We wanted another result. We are to blame, especially from the beginning of the game," Iraola said."After we conceded the goal, you probably had nothing to protect, so you play more freely, we played more bravely, and I think we turned the game in the first half. We finished very well. We tried it in the second half but were unable to score."We had good chances – we hit the crossbar and had good situations we were not able to finish. We definitely deserved a goal."I loved the reaction of my players after going 1-0 down. We finished the first half very well, kept pushing. I loved a lot of moments of the game."We have to keep going. It is very early in the season. Arsenal are in the best of situations, but it is just the start of November. A lot of games to play."Liverpool were beaten 1-0 by Arsenal in the Premier League, but Virgil van Dijk was adamant Alexander Isak should have had a penalty.Virgil van Dijk questioned why Alexander Isak would have to make more of a shirt tug to earn a penalty when there are "50 cameras" around the stadium to see the incident.Van Dijk's comments came in the wake of Liverpool's 1-0 defeat to Arsenal at Anfield on Sunday, with Mikel Arteta's side going three points clear at the top of the standings. Kai Havertz capitalised on Alisson Becker's sloppy pass to score in the 16th minute, but Liverpool responded well to going behind, though they were unable to find an equaliser.Liverpool's best chances came during a frantic spell in the first half, with Florian Wirtz's free-kick hitting the crossbar before Alexis Mac Allister headed over inside the box.The Reds also appealed for a penalty in the opening 45 minutes when Bradley Barcola's cross just evaded the head of Isak, with replays showing the Liverpool number nine was having his shirt pulled by Jurrien Timber, but their protests were waved away by referee Andy Madley and VAR. Isak did not make a fuss about the decision and even stayed on his feet during the incident, though Van Dijk made his feelings known once the final whistle had blown. "I think it was a clear penalty. I've seen it back, and I've seen it being given. It wasn't meant to be," Van Dijk said. "We have 50 cameras."Why does he have to complain when there are so many cameras? Everyone has seen it. In the end, it wasn't given, and we lost the game unfortunately, so well done to Arsenal."Van Dijk's frustrations were echoed by Andoni Iraola, who added: "Especially the Alex [Isak] one. Gakpo was sustained holding, I understand. The Alex one is a clear penalty. "You hold the shirt, we can all see that he holds the shirt. Because he doesn't go to the floor, you are not going to call the penalty. I don't understand it."When asked if Isak should have gone down, Iraola added: "That's the problem we have with the game. Because he doesn't dive and go to the floor."The fact that you are even asking me if he should go to the floor, if he goes to the floor, they call the penalty 100%."It should be like this, but it is what it is. Next time, the managers should tell Alex to go to the floor, otherwise they won't call it."But it was another difficult outing, particularly in front of goal for Liverpool. For the first time on record (since 2003-04), they failed to record a shot on target in a Premier League game at Anfield. It was their 442nd league match played at the venue since the start of the 2003-04 campaign.Liverpool have scored just four goals at Anfield in the Premier League this season, their joint-fewest after five home matches in a top-flight campaign (also four in 1913-14 and 2012-13), though Iraola believed his team deserved at least a goal. "We wanted another result. We are to blame, especially from the beginning of the game," Iraola said."After we conceded the goal, you probably had nothing to protect, so you play more freely, we played more bravely, and I think we turned the game in the first half. We finished very well. We tried it in the second half but were unable to score."We had good chances – we hit the crossbar and had good situations we were not able to finish. We definitely deserved a goal."I loved the reaction of my players after going 1-0 down. We finished the first half very well, kept pushing. I loved a lot of moments of the game."We have to keep going. It is very early in the season. Arsenal are in the best of situations, but it is just the start of November. A lot of games to play."