Arsenal manager Arsene Wenger has suggested that his players were guilty of being "too nice" as they stumbled to a surprise 2-0 defeat against West Ham in their first Premier League game of the season.
Wenger's side appeared to be emerging as title contenders as a strong first half of 2015 saw them lift the FA Cup for a second successive season, while they also showed some sparkling form during their preseason preparations.
Yet that momentum counted for nothing in the first competitive game of the new campaign, with the Hammers securing a win at Emirates Stadium that sparked a fresh round of criticism for Wenger.
Now the Arsenal boss has encouraged his players to toughen up, ahead of their game against Crystal Palace at Selhurst Park on Sunday.
"Sometimes, we are maybe too nice," Wenger told Sunday newspaper reporters. "If you want to say our aggressive level last Sunday was not big enough, then I would agree with you.
"It's maybe linked with the fact we were too confident and that we thought we would win the game anyway and maybe you have to look at West Ham as well. They were advanced on the competitive level to us as they had competitive games in the Europa League. That might have given them a small advantage.
"It's not an excuse and we know that Palace will look to make it difficult for us. That should not be a surprise for us. We just need to be at our best and produce a different performance on Sunday. If we are not ready, we know what will happen."
Back-to-back defeats for Arsenal at the start of this season will be a major blow to Wenger, who has been promoting the importance of a fast start to the season in the last few weeks.
Yet the veteran French tactician is keen to play down the importance of the game against Alan Pardew's Palace, as he looks to dilute the anticipation ahead of his side's second game of the Premier League campaign.
"The reaction to every defeat now is hysterical, but what can I do about that," Wenger reflected. "The West Ham defeat hurt, of course it did. We can ask why it happened, but the reality is the only way to make it better is to respond at Palace.
"The response from people outside of the club to one defeat is not something I can worry about. I keep my mind on the job, that's all. I cannot master the reaction and people are entitled to say they are disappointed if we lose at home and we don't score a goal.
"Football is hugely popular, everyone has opinions. The information everyone has is massive. Everyone knows everything about each game because all the statistics and the data is out there if you want to find it. That is where things have changed in the last few years, but you have to live with it.
"The [West Ham] defeat makes Sunday's game all the more important, of course. It is always about how you respond, so our game at Palace is hugely important."