Jamie Crowhurst bowled his best spell in recent memory and openers Tony McCabe and Mark Ulcigrai smashed half centuries to steer Lake Illawarra to a 10-wicket thrashing of Oak Flats in Saturday's one-day final.

Crowhurst took 5-11 off seven overs as Oak Flats crumbled from being in command at 1-63 to be dismissed for just 139 in 37 overs at Howard Fowles Oval.

McCabe (70 not out) and Mark Ulcigrai (61 not out) completed the belting as Lake won their fourth one-day crown in five years.

"It's one of my best spells for a few seasons," Crowhurst said of his five wicket haul.

"They were hammering us early on but we slowed them down, then the wickets came.

"When I came on we were on top and I bowled straight and full and got a few out. Some days things go your way and it was like that for me."

Crowhurst dismissed the in-form Nathan Brown (40) while the removal of dangerman Kerry Penfold for 45, continued a collapse from which the Rats never recovered.

Ryan Smith cleaned up the tail taking 2-7 while Aaron Henry chipped in with 2-36 for an impressive Lakers attack.

McCabe and Ulcigrai then put on an unbeaten 141 in just 29 overs to add an exclamation point to the first final of the season between the Premier League's top two clubs.

"We love beating Oak Flats, they love beating us," Crowhurst said.

"It's been a great rivalry for a lot of years now and it's always good to win the one-day crown."

Meanwhile, in the First Grade final, The Rail recovered from 7-80 to beat Lake Illawarra (147) by three wickets at Croome Cricket Oval.

In Second Grade, Albion Park's former premiership-winning skipper Graeme Smith ended his career with the club by beating The Rail in the final at Keith Grey Oval.

Batting first Albion Park made 133, then dismissed The Rail for 84.

Meanwhile the unbeaten Lake Illawarra Premier League side will carry the hopes of the region in Sunday's SCG Country Cup quarter-final against Coffs Harbour at King George Oval.

The Lakers must beat Coffs Harbour and then most likely defending champions Hamilton-Wickham in the semi-finals to make the final at the SCG on January 18.

Having come close to the final before, the Lakers are hoping this is their year.