NRL: Canberra Raiders down Parramatta Eels for best start since '05

Canberra have equalled their best start to an NRL season in 14 years after defeating Parramatta 19-0 at Canberra Stadium on Sunday.

The Raiders improved their record to 4-1 and remain third on the ladder after overcoming a frustrating start and keeping a team scoreless at home for the first time since 2013.

Canberra coach Ricky Stuart said the focus this season would be on defence and the club has leaked its fewest points (44) after five rounds since 1990.

"We've got to be consistent. Good footy teams in this competition are consistent," Stuart said.

"You don't see too many perfect performances but that was something we can keep building on and I'll take that effort every week."

The Eels' defeat was compounded by the loss of star recruit Blake Ferguson who left the field early in the second half with suspected broken ribs.

Ferguson had been averaging more than 200 run metres per game this season.

Canberra didn't survive the match unscathed either with lock Joe Tapine going off with syndesmosis.

He will have further scans on Monday.

Parramatta hadn't won in the capital since 2006 and were their own worst enemies in the first half, completing just eight sets, missing 27 tackles and making nine errors.

Eels coach Brad Arthur said he was proud of his side's goal-line defence but conceded they put themselves under too much pressure.

"I think we made somewhere around 200 tackles in the first half," Arthur said.

"We put pressure on ourselves and contributed to the loss through ill-discipline with the ball but they tried extremely hard in defence.

"They controlled the game really well and built pressure and we didn't build any pressure at all."

The Raiders had all the possession and territory in the opening 40 minutes but only scored one try through Josh Papalii, while Jarrod Croker added a penalty for an 8-0 lead at the break.

The home side clicked into gear in the second half with English internationals Josh Hodgson and Elliott Whitehead combining, the latter scoring from a grubber on 49 minutes.

Raiders fullback turned five-eighth Jack Wighton then flew high to collect a Sam Williams bomb to bag their third try in the 61st minute.

Williams sealed the result with a field goal four minutes from time and will likely keep Aidan Sezer out of the starting side for another week.

They'll host Brisbane next Sunday and Stuart is expecting a fired-up Broncos after their 1-4 start to the season.

"They've been bashed around personally and as a club and they're a real strong club who will bounce back and unfortunately it's going to be against us," Stuart said.