A Jonathan Walters own goal in first-half stoppage time has given Chelsea a deserved advantage over Stoke City at the Britannia Stadium interval.
The hosts had managed to keep Chelsea and Demba Ba at bay for 45 minutes thanks partly to some Asmir Begovic heroics.
Ba, who scored a hat-trick against the Potters in Newcastle United colours last season, was making his first Premier League start for the Blues since completing his £7m switch from Tyneside.
However, he was denied a first top-flight Chelsea goal when Begovic saved his well-struck half volley.
The Stoke keeper also produced a fine stop to foil Frank Lampard, blocking with his feet when the Blues skipper looked destined to score from 12 yards.
The best chance of the opening 45 minutes fell Stoke's way but Kenwyne Jones screwed a close-range shot wide after Andy Wikinson's deflected strike fell kindly to him in the box.
Chelsea launched a barrage of attacks as the break approached and eventually broke the deadlock when Walters headed Juan Mata's cross into his own net.
