Arsenal missed a chance to narrow the gap on English Premier League leaders Manchester United with a 0-0 draw against Sunderland on Saturday.
It was the second time in a week the Gunners had failed to live up to expectations.
Last Sunday, they blew the League Cup final against relegation candidates Birmingham.
This time, they missed a series of second-half chances to be held 0-0 in front of their frustrated fans at the Emirates, once again handing advantage to United.
Sunderland, who had lost their last four games, have been a tricky team for Arsenal to beat in recent years, with Arsene Wenger’s men winning just one of their last six matches against the north-east club.
But this result was possibly the most significant as it gives United the chance to move six points clear at the top of the table by beating Liverpool on Sunday.
And Sunderland were probably worthy of a point even though Arsenal were by far the superior team.
The opening 10 minutes belonged to Sunderland as they won a series of corners, pressuring Arsenal into giving the ball away and almost taking the lead when defender Phil Bardsley shot narrowly wide from the edge of the area.
Nicklas Bendtner – preferred in attack to Marouane Chamakh in place of the injured Robin Van Persie – was the focus of Arsenal’s early attacks, but the Danish striker was well contained by Sunderland’s sturdy centre backs Titus Bramble and John Mensah.
And it was Arsenal goalkeeper Wojciech Szczesny who made the first decent save of the game when he leapt to his right to keep out a blistering drive from midfielder Sulley Muntari after 20 minutes.
Arsenal were growing increasingly frustrated, on and off the pitch, as they struggled to create against a well-organised Sunderland side.
But they went close to breaking the deadlock ten minutes before half-time when a Samir Nasri solo run ended in the ball deflecting off Bardsley for a corner.
Then Bendtner had a well-struck overhead effort saved on the line by Simon Mignolet.
Jack Wilshere’s cheeky chip sprung Bendtner clear on goal a few minutes later and the Belgian goalkeeper produced an even better effort to tip the ball over the bar from a stinging right-foot shot.
Sunderland further frustrated Arsenal after the break and Wenger made the bold move of introducing striker Chamakh for ineffective midfielder Denilson with half an hour to go.
And it almost paid an instant return as the Moroccan burst clear and pulled the back to Andrey Arshavin in space, but his shot was comfortably saved by Mignolet.
Sunderland, who introduced on-loan Manchester United striker Danny Welbeck for his first game in two months, had long been happy to waste time and play for the draw.
But a goalless outcome was never going to be enough for Arsenal and there was an air of desperation about their play.
Chances came, though, and they hit the crossbar twice in quick succession.
First, Nasri had a free-kick tipped on to the woodwork by Mignolet, then Chamakh thumped a header at the frame of the goal when he should have scored.
Arshavin then had an opportunity to make amends when Wilshere sent him clear but a shove in the back from Bramble put him off balance and he screwed a shot wide. Fortunately for Sunderland, referee Anthony Taylor did not award a penalty or send off Bramble.
Sunderland were then nearly rewarded for their enormous effort with a late goal as Szczesny made excellent saves from Welbeck and Jordan Henderson.
The referee awarded four minutes of added time to be played at the end and the ball was rarely away from the Sunderland penalty area, but the only half-chance fell to Bendtner and he failed to connect cleanly with a header.