The visitors scored two goals inside the first 13 minutes as Arsenal put in one of the worst first-half performances seen at the Emirates. First Younes Kaboul scored from a deflected free-kick and then Troy Deeney smashed in after good work by Etienne Capoue.
Arsenal were much improved in the second half but could only find one breakthrough, Alex Iwobi scoring in the 58th minute.
Cech, one of the few better performers in an Arsenal shirt, didn’t hold back in his assessment of his team’s display.
‘We had a very bad start,’ he told Arsenal Player. ‘I think we didn’t play well at all.
‘We were second best in the first half. We made so many bad passes, we lost every challenge, we were simply second best.
‘I always say that at this level you cannot play 80 minutes, or 85. You have to play 90 minutes with full concentration and everybody on top of their game.’
Among the worst performers were the defenders in front of him, with Gabriel at right-back in particular being torn apart and Shkodran Mustafi badly at fault for the second goal. Cech was pleased with the reaction in the second half but admitted Arsenal didn’t deserve anything from the game.
‘In the second half we improved, we had a lot of chances. I thought we were brilliant second half, but obviously we only scored one goal.
‘We had chances but the keeper made some very good saves, we hit the bar and we could say we were unlucky in that way. But for the first-half performance, we actually didn’t deserve a little bit of luck.’
Arsenal take on Chelsea on Saturday in a game that could have a huge bearing on the title. Cech admitted the defeat to Watford has put a dampener on that match, with the Gunners failing to close the gap on the league leaders who drew with Liverpool last night.
‘This was a huge setback because this was the game we wanted to win and we wanted to put ourselves in a better position going into the weekend.’