Canberra coach Ricky Stuart has apologised to Raiders fans after his side was belted in an “unacceptable” 53-12 whitewash against Penrith on Friday night.

His Raiders were in the game down just 13-6 at halftime but were obliterated in the second, copping seven tries as the Panthers flexed their premiership muscle and left the Raiders in turmoil at 1-4 for the season.

Doubles for winger Sunia Turuva and centre Izack Tago along with some Nathan Cleary magic ensured the Panthers were always in command at GIO Stadium, Penrith scoring for fun late as the Raiders collapsed defensively.

Stuart refused to outline what had gone wrong for his side but admitted it was “unacceptable”, adding they deserved the criticism that would come their way.

“I’m sure a lot of fans and people out there would like to know exactly what I’m thinking but it’s better we keep it in house and work on it,” he said.

“I’m disappointed for all our fans, it’s going to be a tough week for us all to get through that.

“I can (put it down to something) and that’s what we spoke about. I’m not trying to be disrespectful in my answers, but some of that is best to be left in the rooms.

“We’ll make some decisions in regards to how we fix it.”

Captain Elliott Whitehead was just as scathing, lashing his team’s effort levels in the second-half onslaught.

“The second half just wasn’t good enough, we just didn’t want to turn up for each other and defend,” he said.

“It was pretty embarrassing for us to be in the game at halftime and be blown away like that in the second half.”

Penrith got doubles from Sunia Turuva and Izack Tago, but two unlikely try-scorers drew the biggest celebrations on a night where everything went right for the Panthers.

Hooker Tyrone Peachey crossed for a try in his first game back at the club after five years away, while second-rower Jaeman Salmon scored late in his first game in Canberra since Raiders coach Stuart labelled him a “weak-gutted dog” last season.

Canberra dominated first-half territory but looked one-dimensional on the Panthers’ line, relying on crash balls and struggling to find avenues to the in-goal out wide.

But after looking up for the battle early – and finding a try through Whitehead after a clever Zac Woolford kick – their heads dropped in a second-half whitewash that included three tries in the first 13 minutes.

It was easily the Panthers’ most complete performance of the season, squaring the ledger at 2-2 with both their losses coming by a single point.

“Once we could get a bit of flow and keep the ball, the second half just everything went our way,” Penrith coach Ivan Cleary said.

“It was nice to get a bit of rhythm and score some points.

“These guys have been working very hard for a long time and it’s just good to see them have some fun out there.”

Canberra miss suspended Wighton again next week versus Brisbane and there’ll be little respite on the injury front, with none of Savage, winger Nick Cotric or hooker Danny Levi due back.