While the two blues never fell behind in Sunday's round nine nail-biter the result never looked assured until the full-time whistle blew, thanks largely to CYMS producing arguably their best performance of 2019.

Ethan McKellar's go-ahead try 10 out from full-time ultimately proved the match-winner for the high-flying two blues but it was a bone-crunching moment just 90 seconds before that spurred Hawks' back into the driver's seat.

WATCH: Ethan McKellar scores the go-ahead try for Hawks in the 70^th minute...

They'd trailed virtually the entire game but CYMS continually clawed their way back, a Ryan Griffin try in the 65^th minute drawing the green and golds level at 24-all and swinging momentum in their favour too.

Two tackles after the resulting restart they won a penalty on their own 30, it looked a massive opportunity to march up-field and turn that momentum and position into points, and with them the lead for the first time.

Hawks prop Sam Coyte had other ideas.

CYMS' man mountain Joseph Ualesi wound up from the back fence for the first hit-up after that penalty and was promptly sat down by a massive shot from Coyte, which spurred Hawks into action in a big way.

They forced a knock on next tackle and McKellar scored next to the sticks straight away, Duncan Young's goal giving Hawks the six-point buffer they'd eventually win by.

While it was far from one-way traffic for the remaining minutes the wind was firmly in Hawks' sails, and when Alex Prout held Ryan Griffin up three from full-time, it was clear Sunday was the two blues' day.

"I just stood my ground, braced for contact and hoped he didn't put me on my arse," Coyte laughed after the game, recounting the huge hit.

"He's a massive human and he's hard to handle so I got lucky and just got him in the right spot I think. I had to do it though, I had to do something, I'd given that penalty away and it was silly so I needed to do something to lift the boys.

"I'm just glad we ended up coming away with it, that's such a great win for the guys but it was bloody hard work."

Hard work is probably and understatement, to be completely fair.

The opening 20 minutes was an exhibition in brutality as both sides sacrificed the structural, almost-robotic style of play of the modern era, instead throwing the footy around and simply trying to beat each other into submission.

Both sides had chances during that period but they amounted to nothing, Jacob Sutherland was held up early for CYMS and Nathan Potts not long after for Hawks.

Eventually it was CYMS' line that broke first as Willie Heta sent Rakai Tuheke over with a stunning cut-out ball, Young's attempt successful.

He added another two points shortly after with a penalty goal before Chris Grevsmuhl barged his way over at the other end from close range, one of his two four-pointers for the afternoon.

As the clock ticked ever-closer to half-time both sides missed out on a couple more chances, but Heta made sure of the two blues' last before the break, showing, going and slicing through to score untouched under the sticks.

Young once again duly converted, giving the two blues a 14-8 lead they carried into the second half.

They extended the margin by four more through Eman Rodriguez in the 43^rd minute, after the kick following CYMS' first set of the half went out on the full.

Incredibly Heta, uncharacteristically, plonked his fifth tackle nudge out on the full as he searched for a 40-20 in the next set, and CYMS crossed through Ethan Bereyne on the back of that.

WATCH: Willie Heta slices through for the first of his two tries on Sunday...

Steve Morris followed that try with a successful 40-20 and Grevsmuhl scored his second, McAlpine's kick sensationally deadlocking the clash at 18-all in the blink of an eye.

As he did the in the first half Heta waltzed through to score his second just minutes later though, once again giving Hawks the lead.

That lead last 10 minutes before Griffin burrowed over, as he so often does, from dummy-half. McAlpine slotted his fourth goal of the afternoon to once again lock the clash up and set up a grandstand finish.

Then Coyte pulled off what, in hindsight, became a match-winning defensive effort.

The victory keeps Hawks in a share of the competition lead with defending premiers Bathurst Panthers, and is their fifth on the trot since suffering their only defeat of the season to the Mudgee Dragons

Incidentally the Dragons drop out of that share for the lead thanks to their upset loss to Lithgow on Sunday afternoon.

"Hopefully there's no stopping us now. We're going along well and there's plenty of hard work to still do, but it's positive signs," Coyte smiled.

It wasn't all bad for the green and golds though, who remain adrift of the top five after the defeat, because they were strong for the most part on Sunday.

"It was a step in the right direction, for sure," CYMS player-coach Dom Maley said.

"We can only take so much from it because we didn't get the win we wanted but credit to Hawks, they're a good side. One big thing was the penalties we gave way early, the penalty count was 6-2 early at one stage and you can't give good teams ball like that.

"But it was certainly a lot better than (the big defeats CYMS suffered to) Bathurst Panthers and Mudgee, there's good signs from it.

"It was good having a couple of big bodies in Chris Grevsmuhl and Joseph Ualesi back, they were both excellent, so we'll just need to keep building on it.

"But the discipline early and a few errors in the clutch probably ended up costing us there."