Gary Haines reports from St James' Park

Chris Powell hailed his side's defensive durability after the Addicks clinched a hard-fought 1-0 win at Exeter City on Saturday.

The Charlton chief presided over a fourth successive clean sheet as the League One leaders made it 12 points from a possible 12 at the start of 2012.

This latest win was built on firm foundations once more, with more than an element of luck involved in what proved to the game's decisive moment.

Danny Green claimed the winner after his cross from the right caused untold problems for Artur Krysiak, with the ball eventually crossing the line via the keeper and the bar.

And the result, coupled with Huddersfield Town's draw at Tranmere Rovers and the fact both Sheffield clubs were in FA Cup action, saw the gap at the top extend to nine points.

Powell said: "I always knew that following the Sheffield Wednesday and Sheffield United games, coming to a place like Exeter would be tough.

"They always play good football and I knew the atmosphere wouldn't be how it was in the previous two games, and it was up to us to manage that.

"The first half was very flat and there was no real atmosphere and no real tempo from both teams.

"I asked the boys to lift that and do better with our attacking play," he added.

"I felt at the back we were fairly comfortable. It was only really of our own making if Exeter had any chances.

"It was just a case of giving a bit more in the second period and we got the goal, whether it was meant or not.

"It's another win, though, and another three points in our quest to get some success this year."

On the goal from Green, a clipped cross from the right that left Krysiak all of a dither before sneaking in, Powell said: "It does look as if was over the line.

"He [Green] wants to claim it, and I'll gladly give it to him."

When asked whether it was a sign of the times with the leaders enjoying the kind of luck that befits such a lofty league standing, Powell countered: "I think sometimes it's a reward for positive play, and throughout the second period we were in the ascendancy a lot more.

"It obviously helps us in that instance with regards to the cross-cum-shot and the goal.

"So I'm really happy that we've come away from a really tricky game with three points.

"Obviously, after the two Sheffield games everyone is expecting us to ease to wins against teams that are in the lower reaches, so it's important that we still set up right and are defensively strong, which we have been with four clean sheets so far in 2012.

"Then things will go for you if you are still being positive and trying to attack your opposition's goal. So I'm very happy with the outcome."

With two teams that had conceded just one league goal between them in the calendar year, Powell had tipped a tight game in the build-up.

And he noted: "Because of the way Exeter have been going recently, I knew there wouldn't be a lot of goals today.

"But in the first half, I felt we didn't really play with a purpose and were a little bit flat.

"It's expected because of the two huge [Sheffield] games that took care of themselves with regards to getting us up for the game.

"It was up to myself, my staff and the players themselves just to gee one another up because I felt if we did that we could get the goals and the result that we wanted, and that's what happened

"For us to get clean sheets, that is what good results are built on and good seasons are built on, being defensively strong.

"I want my players to really work hard to keep a clean sheet, because I know there is quality at the other end."

Finally, there was a welcome return to action for midfielder Dale Stephens at St James' Park as he entered the fray as a late substitute.

Stephens came on for Green for the closing eight minutes for his first senior action since mid-October and his subsequent ankle surgery.

And Powell was delighted to have him back, stating: "Dale is a very good player, but I didn't want to rush him straight back in, because he's been out for a long while.

"He adds quality, he adds forward passing, he adds composure and he always seems to do the right thing when he's on the ball.

"I'm glad he came back in and contributed and hopefully now that will get him up to speed for the rest of the campaign."