Robert Pires got both goals as Arsenal survived the threat of Cardiff to progress to the FA Cup fourth round.
The holders took the lead when Jose Reyes found Pires and he added the finishing touch.
Pires got his second 12 minutes later after another flowing move involving Robin van Persie and Dennis Bergkamp.
But Cardiff put the Gunners under severe pressure in the second half and Cameron Jerome scrambled a goal back to make it a nervy finish.
Arsenal boss Arsene Wenger opted to rest some of his star names with the likes of Thierry Henry, Jens Lehmann, Sol Campbell and Kolo Toure given the day off after a strenuous Christmas.
Youngsters Kerrea Gilbert and Johan Djourou were both handed starting places and Arsenal's inexperienced defence were nearly caught out within 30 seconds of the start.
Neal Ardley's pass split the Arsenal defence and Cardiff forward Jerome beat Manuel Almunia to the ball but his instinctive lob landed just over the bar.
But six minutes later Cardiff's dream of an upset took a nosedive.
The home side strung together a move of 13 passes that featured Reyes teasing the home defence before sliding a through ball for Pires to guide past goalkeeper Neil Alexander.
Cardiff's height continued to ask a few questions of the Arsenal backline but too often the Gunners were quickest to pick up the bits and pieces.
The second goal was another move straight off the Highbury training ground.
This time it was Van Persie who split the defence to find Bergkamp, who slipped it inside for Pires to sidefoot past Alexander.
But it was a different Cardiff side that came out for the second half and they could have grabbed a goal back early on if Darren Purse had not swung and missed with just Almunia to beat.
Top scorer Jerome showed why he is rated so highly when he raced away from the Arsenal defence to find Kevin Cooper, but Djourou saved a certain goal with last-ditch block.
Whitley met a ball over the top with a wonderful volley that was kept out by Almunia at full-stretch and then had a penalty appeal late on when his effort was blocked by Philippe Senderos' arms.
They got their rewards when Ardley's corner was flicked on by Neil Cox and Jerome managed to get the final touch, although there were doubts about whether the ball crossed the line.
There was even time for Cardiff to threaten an equaliser but Almunia, and Arsenal, just managed to hold on.
Arsenal: Almunia, Lauren, Senderos, Djourou, Gilbert, Pires, Silva, Flamini, Reyes (Owusu-Abeyie 45), Bergkamp, Van Persie (Larsson 77).
Subs Not Used: Poom, Hleb, Lupoli.
Goals: Pires 6, 18.
Cardiff: Alexander, Weston, Loovens (Koskela 64), Purse, Cox, Barker, Ardley, Cooper (Lee 89), Whitley, Ledley, Jerome.
Subs Not Used: Margetson, Darlington, Mulryne.
Booked: Whitley, Loovens.
Goals: Jerome 87.
Ref: M Atkinson (W Yorkshire).