Arsenal manager Arsene Wenger says his side's performance against West Ham United was not good enough.
The Gunners suffered a shock home defeat against the Hammers on Sunday afternoon, days after beating Chelsea to retain the FA Community Shield.
Goalkeeper Petr Cech was largely at fault for both goals although questions will be raised about the fitness level of all Arsenal players who struggled to keep up with Slaven Bilic's men especially in the second half.
"I think our performance was not convincing," Wenger told reporters.
"On the two aspects of our game, going forward and defending. Overall we were punished. On top of that, I feel we gave two very cheap goals away and they were at the wrong moments - just before and after half-time with two minutes to go, and just after half-time.
"We gave ourselves a mountain to climb. West Ham looked a bit sharper than us, more advanced in preparation than us. In the end we wanted, but it was not convincing, not agile, not quick. Our passing was too slow and in the end we were punished.
"I haven't spoken to him [Petr Cech] yet.
"I can't see many individual convincing performances today so it's difficult to single someone out.
"[New signings?] I would like to think that we are responsible to buy the players and the coaches, not the media. When you're a pro footballer, you have to face your responsibilities and not always look at something else.
"Today we have to look at ourselves and think we were not good enough and not to think that these kinds of things are solutions for us. We were not good enough, we were not convincing.
"And that's basically it. West Ham played well. Congratulations to them and hopefully we can bounce back quickly. Again, I can only repeat what I already said.
"If an exceptional solution turns up, we'll do it. But after a defeat like that, it's important not always to think we take a solution from outside."