Ben Amos wants Charlton to rediscover their “nasty” side during the Christmas period.

Sixth-placed Charlton travel to high-flying promotion rivals Blackburn and Wigan this month.

Karl Robinson’s men have lost two of their last three league games and haven’t kept a clean sheet since October.

But goalkeeper Amos believes the Addicks will turn their form around.

The Bolton loanee said: “We want to be able to put teams away four, five nil. We’ve got the capability in the team to do it. It’s not quite clicking at the minute for whatever reason.

“If we can get back to being resilient again, keeping clean sheets then it will at least give us a platform to score some goals.

“At the beginning of the season, we won a few games we shouldn’t have won, but we were able to grind it out. Now it’s going the other way where we’re on top of teams but not quite winning the games.

“We’ve got to put that right and get a little bit more nasty again when it’s going against us, roll our sleeves up and put teams away.

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“We just need to do the basics right and be more aggressive than the opposition. Sometimes you’ve got to win ugly when you’re not playing well. At the moment, we’re not playing well but I’m sure it will change.”

Despite a dip in form, Charlton are just six points away from the top two.

And Amos insists automatic promotion is still a realistic aim – but says the club need to make a statement of intent in the upcoming weeks.

He added: “If you’re in the top six by Christmas, there’s still a lot of football to be played. So there’s nothing to worry about as such.

“We’re aware we’ve got to hit a good run of form going through the Christmas period. But the challenge is there for us and we’ve got to rise to it.

“If you plan on getting automatic promotion, you’ve got to go and win those games [against Blackburn and Wigan] at the end of the day.

“You can maybe afford to drop points here and there but not very often. So throughout this period, we’ve got to pick up some big wins.”