Canterbury produced its most insipid showing of the year at ANZ Stadium as the Panthers made it three wins on the trot to keep the top-eight clubs looking over their shoulder with Penrith's early season woes now seemingly in the rear-view mirror.

But they were helped by an ordinary Bulldogs side which struggled to look after the ball and gave away too many penalties in a performance that has left them just third from bottom in the NRL.

"It wasn't acceptable, certainly at a first-grade standard, the players accept that and they know that," Hasler said after his 350th NRL game as a coach.

"Everyone's got to work harder. We were down on a bit of energy at the start as well.

"We can't use excuses. Sure we've got players backing up [from State of Origin], sure we've got players out.

"Our discipline as far as penalties are concerned in the wrong part of the field position is also a lot to be desired at the moment.

"[There were] some really bad poor defensive lapses particularly some missed one-on-one tackles which is unlike us.

"When you're continually on the back foot because you can't control possession or get an even flow of possession then you're faced with doing more defensive work and it accumulates. Today we just didn't manage that well enough."

The Bulldogs' afternoon started poorly with Penrith captain Matt Moylan, in his new role as five-eighth, laying a big shot on Canterbury's Kerrod Holland who dropped the ball 15m out from his own goal line.

After four minutes Penrith were on the board, and it set the tone for the afternoon.

"We need to have a good look at ourselves individually and the way we apply ourselves at training and come out next week," Bulldogs captain Aiden Tolman said.

"Last week the effort was there. This week, right from the start, error on the first carry, they're attacking our try line, we couldn't get out of our own end.

"Their defensive effort was pretty good, they were bouncing through the ruck and we were on the back foot the whole game."

Tolman was deputising at captain for James Graham who missed the game with a neck injury, but he's expected to be back next week.

Hasler also hinted playmaker Josh Reynolds could be back early from a hamstring injury against St George Illawarra next round.

"He'll be reviewed early in the week so we'll have a look at him," Hasler said.

"His experience of course and definitely what he brings as far as energy is definitely something that we're missing at the moment, but it's not an excuse."

As for the Panthers, they head into next weekend's clash against the Canberra Raiders just two points shy of the top eight, and coach Anthony Griffin suggested he'd persist with Moylan at five-eighth.

"He was great there today so I don't see any reason to change it," Griffin said.

"His first play of the game defensively set the tone for the whole team for the day. We had a real focus on coming here and being able to do a job defensively.

"For the team to see their captain fly out of the line like that and get an error in the first set, that set the tone."

Mitch Rein played his first NRL game for the Panthers and scored two tries, while Josh Mansour returned after seven months out with a knee injury.