Manly coach Des Hasler feels his team will benefit from a dogged clash with the Raiders after they overcame the absence of Tom Trbojevic to scrape out a 19-18 win.
Hasler's men trailed 12-0 at half-time after Canberra dominated with some committed defence but found enough of a groove to sweep home and put themselves in the top four for the time being.
A 78th-minute field goal from Daly Cherry-Evans ended up the difference as Charnze Nicoll-Klokstad scored with 30 seconds to go.
"We probably needed that game, actually, and it's come at a good time," Hasler said after Friday's match at Suncorp Stadium.
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It was the fourth time in nine games this season that Manly have won without their superstar fullback Trbojevic, who Hasler confirmed will return from a cheekbone injury against Canterbury next week.
"We were probably guilty of turning over the ball," Hasler said.
"I thought the start was OK, but [we] probably enabled them some field position too easily. And they're a good side, Canberra, so if you put enough pressure on yourself they manage to find points.
"And we did that. We sort of talked about that and addressed a few things at the half-time break. To the credit of the Manly side, our side, they went out and we executed what we needed to.
DCE. Ball. String.
"They're a hard side to play and we knew it was going to be a real grind type of game against Canberra. They've got a lot of big bodies and they break a lot of tackles."
Sea Eagles second-rower Haumole Olakau'atu and centre Moses Suli, who made 208 metres from 18 runs, were particularly destructive.
"Losing Brad [Parker] with a HIA [after last week], he had a whale of a game, Moses," Hasler said of the 23-year-old Suli.
While Manly are currently in fourth spot, the Roosters are also on 30 points and face the Dragons on Sunday while the Eels sit on 28 ahead of their clash with the struggling Cowboys on Saturday.
There was late drama after Nicoll-Klokstad's last-ditch four-pointer with Rapana rushing through the conversion and then Sea Eagles forward Josh Schuster being sin-binned for a professional foul.
That allowed the Raiders to advance downfield from a penalty kick, but Rapana scuffed a last-ditch two-point field goal shot.
Jake Trbojevic with a huge defensive play
It leaves Canberra in ninth place having missed a golden chance to move into seventh with only two rounds before the finals.
Nicoll-Klokstad emerged unscathed in his first game since injuring his neck in round five, playing fullback for the last 25 minutes.
The custodian didn't have a happy entrance to the match, however, spilling the ball in his first carry from a kick return and allowing Manly an opportunity to draw level in the next set.
The willing Raiders were led by front-rower Joseph Tapine, who had an immense first 30-minute stint with 110 metres from 12 carries.
And it was a one-on-one strip from Tapine on Suli that laid the platform for the Green Machine to strike the first blow.
Centre Matt Timoko displayed great skill as he flicked a pass to winger Harley Smith-Shields, who scored in the 11th minute.
Even as errors crept in, Canberra kept the Sea Eagles at bay with Olakau'atu denied a try due to obstruction.
Olakau'atu hits and spins his way over
A Sam Williams penalty goal extended the underdogs' advantage before Bailey Simonsson crossed in the left corner to put them in command after 32 minutes.
As expected, the Sea Eagles came out in the second half with renewed energy and scored after three minutes as Olakau'atu barged over from close range following a devastating Suli break.
Still, the tense battle continued. But cracks emerged for Canberra after Nicoll-Klokstad's unfortunate error.
Manly touched down through Morgan Harper on the following play as Cherry-Evans boldly kicked and the bounce sat up for Jason Saab, who basketball-passed inside to assist his centre.
This time, Manly seized the momentum and hit the front in the 63rd minute as Cherry-Evans placed a cute grubber that was plucked by a rampaging Curtis Sironen en route to the in-goal.
Cherry-Evans's composed call to slot a field goal, as has been the case so many times in his storied career, was crucial.
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