The Panthers will go into Sunday's NRL clash with Gold Coast having let in just 11 tries this year, the same amount the Titans have conceded in the last two games alone.

But it wasn't always this way for Penrith.

The club overhauled their defence at the start of 2019 on Ivan Cleary's arrival, as Cameron Ciraldo went back from interim coach to head of defence.

After 10 rounds they were the worst defensive side in the NRL, sitting dead last on the ladder and having let in an average of 24 points per game.

Last year it improved dramatically before becoming the best defensive side over the opening nine rounds since St George in 1963 this year.

"The system they're using at the moment they haven't been doing that for a long time so that's taken a bit of work," Cleary said.

"It's a lot of hard work we've put in.

"It's a whole-of-game approach and we've been fortunate enough to dominate possession in most of our games that that helps.

"We definitely value defence.

"Cameron Ciraldo our defensive coach does a fantastic job. Credit to the boys because they you know they put a lot of work in."

While Penrith's entertaining attack is often noted for being the result of years of players coming through juniors together, so is their defence.

Just 19 players have bust their line at any point this year, while they have also missed the least tackles of any team.

"That connection helps anything you do, whether it's attack, defence on the field or off the field," Cleary said.

"Up to this point, I've been pretty happy with it. Hopefully we'll do it again tomorrow."

Meanwhile Cleary admitted he wrestled with the decision to put Matt Burton in the centres ahead of Paul Momirovski.

Canterbury-bound Burton has been a star since coming into the Panthers' starting side, but Momirovski was solid in the opening five rounds before copping a ban.

"Yeah, it was actually (a tough choice). Like all the decisions we make, we just do what's best for what's best for the team," Cleary said.

"Matt's a really important part of our club this year and that doesn't change."

Australian Associated Press