Charlton manager Chris Powell saluted his back four after an impressive 4-0 victory at relegation-threatened Chesterfield.
A Bradley Wright-Phillips hat-trick and a Johnnie Jackson strike took Charlton 15 points clear at the top but Powell was just as happy with a 14th clean sheet of the campaign.
Charlton have now won 12 league games on the road to equal a club record and Powell said: "Clean sheets are the key and being an ex-defender myself I wanted us to be right."
"Strikers win games but defenders win promotions and championships. It's usually the case that teams with the best defensive records are in the top places. It's a mantra we have, we don't want to be beaten and we don't want to concede goals."
But Powell was delighted Wright-Phillips was again on the scoresheet after he ended a goal drought stretching back to November on Saturday.
There was some debate about whether his third went in off a Chesterfield defender but Powell said: "I would love him to be given all three. I think a weight was lifted off him on Saturday and he's been bouncing around. He's kept his own counsel and we have kept believing in him."