The Lakers have now won five-straight trophies after sweeping last year's three competitions and winning the one-day final earlier in the year. 

Batting first, the Rats were bowled out for 126, with Lake Illawarra reaching their total in the 19^th over. 

Lake Illawarra captain Mark Ulcigrai said the victory was built on the back of a superb bowling and fielding performance.

"It's excellent to have won the Twenty20 trophy," Ulcigrai said. "I thought our fielding was outstanding, we did drop a couple of catches, but in the end they didn't cost us.

"It was a really good performance in the field and with the ball, we bowled pretty tight through the middle overs to pull them back after they got off to a fast start.

"It was a tricky total to chase, 126, especially on that field, there weren't many boundaries on offer. Ryan Maguire and Kerrod White combined for a 78-run partnership, they were really good and then Luke Fleming came in to finish it off."

With two trophies now secured for the 2018-19 season, the Lakers have their eyes set on the biggest trophy of the season, the two-day crown. 

"Absolutely, we want the two-day trophy. We're playing Oak Flats now in the two-day competition and we're hoping to wrap up the minor premiership. 

"Who knows what the weather's going to do, we always want that insurance policy in the finals."