Thibaut Courtois believes Chelsea needed the "wake-up call" of losing to Burnley to show them the effort that is required to retain their Premier League title.
Antonio Conte's side recovered from that shock opening weekend defeat to beat London rivals Tottenham 2-1 at Wembley on Sunday.
Marcos Alonso struck twice – including a sweet free-kick – to seal three points for Chelsea, despite the fact Spurs dominated for long periods and levelled courtesy of a Michy Batshuayi own goal.
Chelsea had captain Gary Cahill and Cesc Fabregas suspended for the game after their red cards against Burnley, while Eden Hazard is still missing through injury.