Sunderland fullback Danny Collins says the defence has benefitted from the arrival of Jonny Evans and Phil Bardsley from Manchester United.
Collins told the Sunderland Echo: "The new lads have come in and helped us straight away. Jonny, we obviously knew from last season when he was great in the Championship.
"He's only a young lad but he has a mature head on his shoulders and is an excellent organiser as well as everything else.
"Then you've got Phil Bardsley, who has just come in and hit the ground running straight away.
"He's brought great energy to the side. He's been rock-solid so far and he likes to get upfield whenever possible.
"Having someone like that in the side helps ease the pressure on players. He's a right-back who wants to play right-back, whereas quite often this season we've had players who've gone in there as a stop-gap.
"He's come from Manchester United, so you know he's going to have something about him. And with Phil settling in straight away and looking comfortable it's brought extra balance to the side.
"All defences take time to settle once they're put together. But I think overall they've settled in quite quickly and, fingers crossed, we can go on to become a much meaner defence.
"We know that if we can keep clean sheets or restrict the amount of goals scored we've got a real chance of picking up more points in the games ahead."