Chelsea captain Gary Cahill believes that Antonio Conte's side took a huge step towards regaining the Premier League crown after they beat Southampton 4-2 at Stamford Bridge.
Diego Costa ended his goalscoring drought with a well-taken double after Cahill's header had restored Chelsea's lead - given to them by Eden Hazard's early strike - on the stroke of half-time.
The victory takes Chelsea seven points clear of second-placed Tottenham, who face in-form Crystal Palace on Wednesday, and England defender Cahill - who missed out on the FA Cup semi-final win over Tottenham through illness - knows the title is now firmly within the Blues' grasp.
AS IT HAPPENED: Chelsea beat Southampton to maintain Premier League charge
"It feels like a massive step to be honest," Cahill told Sky Sports. "It's the first time for a long time that we've played first so we're delighted to get the win.
"I had a difficult week with a bit of gall bladder pain but the lads didn't miss me against Tottenham at Wembley. I'm just glad to get back out there.
"We've got a big game this weekend, a difficult game [at Everton]. We need to rest up for that. We can watch the game tomorrow with our job done."
Cahill's goal came after his former Chelsea team-mate Oriol Romeu had levelled proceedings, and the England international acknowledged his header came at the ideal time.
"I just sniffed out a second a ball, Marcos [Alonso] has put it back over and it's a ball that, for a striker or a defender, is dying to be attacked," Cahill added.
"I'm sure it deflated them – I've been on the end of those myself. It was great timing."
READ MORE: Hazard not right for Chelsea captaincy
Hazard may have missed out on the PFA Player or the Year award to team-mate N'Golo Kante, but the Belgian's fifth-minute effort set the tone for Chelsea's dominant display on Tuesday, moving him on to 15 goals for the league campaign.
"It's always good to score, to create a lot of chances. We scored four beautiful goals, Tottenham play tomorrow so we put pressure on them," Hazard said.
"To be fair I just want to take the trophy at the end of the season. If my goals help the team to win the games I'm happy."