Dapto Greyhounds made it three sudden-death victories in a row and beat minor premiers Lakeside Eagles to clinch the Illawarra men's Premier League squash competition.

Greyhounds finished third in the regular season, beat Dapto Bulls in the minor semi-final and upset the second-placed Collegians, before their thrilling victory over Eagles in the grand final at the Dapto Squash Centre.

It was Eagles' first grand final loss in more than three years which included a run of five premierships in seven competitions.

The annual Premier League competition comprises of an autumn and spring competition with Eagles having made six of the last seven deciders.

"It was a fantastic grand final and credit to Greyhounds for the way they played," Eagles veteran Troy Mountford said.

"Mark Robertson was the difference with his win but it was a very close match."

Greyhounds elected to begin the decider with a battle of the respective No 2s, with Greyhounds' Dane Sephton beating Mountford three games to one.

Eagles then sent on their ace, NSW No 4-ranked Brett Hyland, who won a tight rubber 3-1 against Daniel Condie, who was in the match until he aggravated a calf injury.

In the battle of the No 3s, Mark Robertson then put Greyhounds ahead with a 3-0 win over Jonothan Cook.

With a two rubbers to one advantage, Greyhounds' No 4 Stacey Sephton then claimed the one game required to seal victory in a 3-1 loss to Garry Piggott.

The men's spring competition begins in a few weeks.