Chelsea cruised to a comfortable victory over Sunderland as Claudio Ranieri's side made it seven matches unbeaten.
William Gallas's volley established a second-half lead for Chelsea after a first half of stubborn resistance by Sunderland.
Marcel Desailly and Jimmy Floyd Hasselbaink added a late goal each to make the points safe.
Chelsea would eventually finish fourth that season as Manchester United lifted the title, while Sunderland were relegated in 20th place.
Aaron Ramsey scored twice on his return to former club as Arsenal moved seven points clear at the top of the Premier League.
Cardiff City went into the match in confident mood following a 2-2 draw against Manchester United, and Fraizer Campbell forced a fine save from Gunners 'keeper Wojciech Szczesny with Arsenal leading 1-0, but they eventually had no answer to the Gunners' passing game.
After Ramsey's first-half opener, Mathieu Flamini doubled the visitors' lead with four minutes left, before ex-Cardiff man Ramsey made 3-0.
Arsenal would eventually finish fourth that season behind Premier League winners Manchester City, Liverpool and Chelsea.