Cesc Fabregas found himself on the losing side in a Premier League fixture in which he has scored for the first time as Chelsea came unstuck against Crystal Palace.
The Spain international had previously netted in 42 English top-flight games without coming unstuck.
That run started at Arsenal and was continued after the World Cup winner returned to British shores at Stamford Bridge in 2014.
Fabregas opened the scoring in his most recent appearance, with the deadlock broken against Palace inside five minutes.
He was, however, to see the Eagles hit back through Wilfried Zaha and Christian Benteke to claim a stunning derby success and inflict just a fourth Premier League defeat of the season on the Blues.
Chelsea’s lead at the top of the table has now been cut to seven points, with capital foes Tottenham their closest challengers.
Fabregas, meanwhile, now has six goals for the season in all competitions and has netted in three successive Premier League home games.