Chelsea cling on to win five-goal thriller at Palace
Frank Lampard's men edged closer to sealing a place in next season's Champions League as a seventh win in eight games takes them two points ahead of Leicester, who travel to Arsenal later on Tuesday, and opened up a five-point lead on fifth-placed Manchester United.
The Blues were fortunate when opening the scoring at Selhurst Park as former Chelsea captain Gary Cahill fell to the ground clutching his hamstring to allow Willian to tee up Olivier Giroud for his fourth goal in six games.
Chelsea have already stated their intent to move up a level next season and challenge Liverpool and Manchester City for the title with the signings of Timo Werner and Hakim Ziyech.
Their arrival could have put Christian Pulisic's place in the team under threat, but after an injury-disrupted start to his first season in England, the American is beginning to flourish.
Pulisic's form has led to comparisons with Eden Hazard, the man he replaced at Stamford Bridge, and the Belgian would have been proud of Chelsea's second as the 21-year-old skipped past Joel Ward and hammered in off the inside of the near post.
Chelsea appeared to be cruising towards victory and only a great save from Vicente Guaita turned Willian's shot wide from Pulisic's layoff as the visitors threatened to run riot.
However, as so often this season, Lampard's men failed to capitalise on their dominance and were suddenly on the back foot when Wilfried Zaha thundered a shot high past Kepa Arrizabalaga from long range for Palace's first goal in four games.
Chelsea looked to have sealed the three points again when substitutes Ruben Loftus-Cheek and Tammy Abraham combined for the latter to restore a two-goal cushion 19 minutes from time.
Just over a minute later, though, Palace were back in the game when a brilliant move culminated in Patrick van Aanholt squaring for Christian Benteke to tap in just his second goal of the season.
Questions remain over whether the Chelsea defence will be strong enough to maintain a title challenge next season and they were left clinging on in stoppage time as Scott Dann's header came back off the inside of the post and only a last-ditch challenge from Kurt Zouma denied Benteke a second.