Arsenal manager Unai Emery Photograph:( Reuters )
Teenager Declan Rice scored his first goal for the Hammers to dent Arsenal's top-four hopes.
Arsenal head coach Unai Emery said that the team "lost a very great opportunity to take three points" after his side lost 1-0 at West Ham in the Premier League on Saturday.
Emery expressed discontent after the defeat saying Arsenal did not deserve to lose, saying: "I think maybe the result is not one result we deserved."
"But in the game plan, in the control, we like to improve our way there," he added.
Teenager Declan Rice scored his first goal for the Hammers two days ahead of his 20th birthday to dent Arsenal's top-four hopes.
In the match against West Ham, Arsenal began brightly and had several chances but ended up losing.
Emery said, "We needed to attack more better, but they defensively also worked well. We created some chances, but it isn't enough for thinking we can win."
"First half maybe the first 20 minutes when we created some chances is the moment we kind of started to think to win this match, but after (it) is difficult because we didn't impose in the 90 minutes all the things we wanted," Emery added.
Emery also defended Mesut Ozil's omission from the squad. Ozil, Arsenal's highest-paid player, has returned to full training over the last week following a knee injury.
He was in defiant mood when asked why Ozil had not featured at all on Saturday, saying: "I decided the idea of the players that I think are the best for this match.
"We win with him, we lose with him. I think it is not one player (which means) we can't win or lose."
"Today the players who were here are the players who deserved to be in this match. We could've won or lost."
"We continue working with every player because they are all important, but today the decision was to come with these players," he concluded.
It was fifth league defeat of the season for the fifth-placed Arsenal, which failed to score for the first time in 21 league matches and have now lost consecutive away games.