Cardiff were a match for Arsenal until the latter stages of the tie
Cardiff produced a superb performance to hold Arsenal to a goalless draw in the FA Cup fourth round at Ninian Park.
The Bluebirds dominated the early stages but wasted good chances, with Ross McCormack, Joe Ledley and Paul Parry all failing to hit the target.
Nicklas Bendtner wastefully headed over for Arsenal late in the first half.
Emmanuel Adebayor scuffed a great chance as Arsenal improved after the break, though McCormack did clip the Arsenal crossbar with a free-kick.
Cardiff were hanging on in the latter stages of the game but they fully deserved to take the tie to a replay.
Dave Jones' team, beaten finalists last season, really took the game to Arsenal in the opening half, playing with a desire absent in their more illustrious opponents, and the high-flying Championship side should have taken at least one of their chances.
McCormack headed wide from 10 yards and Jay Bothroyd shot over from outside the box while Ledley failed to hit the target with a volley from seven yards after a precise cross from Parry.
An error from Bakary Sagna then gifted possession to Parry and the 28-year-old really should have tested Lukasz Fabianski in the Arsenal goal after breaking into the penalty area but he again shot over.
The Bluebirds received magnificent support from the home crowd, while Arsenal struggled to play their fluent passing football.
Aaron Ramsey in particular found it difficult on his return to the club that sold him for £5m last summer and he was replaced by Abou Diaby after 59 minutes.
The Gunners, with five changes from the team that defeated Hull last weekend, looked rattled but came close to punishing Cardiff's profligacy in front of goal when Robin van Persie picked out Samir Nasri midway through the opening half.
Nasri had time to pick his spot and opted to shoot across goal but he was denied by Peter Enckelman.
The opening half appeared to be petering out when Cardiff launched another excellent attack. The Bluebirds had a penalty appeal for a handball against young defender Kieran Gibbs correctly turned down by referee Martin Atkinson, while Ledley saw his shot blocked by one of his own team-mates.
Arsenal countered dangerously but Bendtner's first touch was heavy and his subsequent shot was blocked. The striker should have tested Enckelman from the corner that followed but headed over.
Van Persie shot narrowly wide with a free-kick and McCormack forced Fabianski into action with a terrific long-range strike as both teams pursued the opening goal after the break.
Cardiff almost gifted Arsenal the opener when Mark Kennedy inadvertently directed a cross towards his own goal but Enckelman was alert to the danger.
The Bluebirds keeper played a more involved role in the match as Arsenal started to dominate possession and he twice denied Van Persie from tight angles.
Adebayor, who had replaced the disappointing Emmanuel Eboue, should have scored when the ball fell to him at far post but he made an awful contact while Enckelman saved a long-range strike from Nasri.
Arsenal looked the most likely to score a winner, though McCormack's free-kick almost snatched victory for Cardiff in the final minutes.
Arsenal boss Arsene Wenger on the forthcoming replay:
"We could do without it, 100%, but let's not complain because we play football.
"It's one more game to play. If that's the price we have to pay to stay in the hat, we're happy to do it.
"We are short at the moment and cannot rotate much. I could rest a few players in this game but not as many as I had wanted."
Cardiff City boss Dave Jones on the replay: "My players would rather play than train. They're always moaning that they have got to train, so it doesn't really affect us.
"Arsene Wenger is fighting on three fronts at the moment so if he wants to give me the game, we won't go down to the Emirates although the chairman wouldn't be happy.
"It's a massive payday."
BBC Sport Player Rater man of the match: Arsenal's Robin van Persie on 7.36 (on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.
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