After Charlestown posted 7-129 from their 40 overs (reduced to 119 after a rain interruption), the game was in the balance after Wests lost openers Aaron Wivell and Joey Price with only 35 runs on the board.

King proceeded to compile an ice-cool 48 not out, sharing an unbroken 76-run stand with Daniel Andrews (28) and sealing victory with a six.

It was the fourth final that the left-hander has dominated.

In 2017-18, he helped end a 52-year title drought by scoring 93 not out as Wests beat Merewether in the two-day decider.

Last season he blasted 125 in the Rosellas' Locker Cup final triumph against Hamilton-Wickham, an innings he arguably surpassed months later when he scored 68 not out to clinch a thrilling one-wicket win against Belmont in the two-day final.

After Sunday's win, King said big occasions seemed to bring out the best in him.

"I suppose it's the intensity of the opposition that lifts your batting," he said.

"Charlestown were up for up for it today, with the ball.

"When you walk out to bat and the opposition are all up for it, it takes you to another level.

"When Dan Andrews came out to bat, it was just a case of trying to lower our target. We took it 10 runs at a time and cruised home in the end."

King said he took confidence from his past performances in pressure situations.

"Yeah, I think so, but it's more just knowing that the other boys have done it before, as well," he said.

"Even though we only lost a few wickets today, there was a stage when we could have crumbled.

"But we've probably learned how to take the game deep and put the pressure back on the opposition and see who folds first."

A modest King said the real heroes for Wests were their bowlers, who put Charlestown on the back foot from the outset.

"The first session was when we won it," he said.

"I think they were 30 off the first 20 overs, so we won it with the new ball."

After winning the toss and opting to bowl first following overnight rain, Wests struck a crucial early blow when young speedster Jeremy Nunan removed Charlestown skipper Daniel Arms for one.

The visitors were soon struggling at 4-29, but rearguard actions from opener Michael Richardson (41) and Aaron Winchester (32) and Parth Shah (28 not out) gave them a fighting chance.

Wests' bowlers shared the wickets but paceman Brad Aldous (2-22) and legspinner Aaron Bills (2-33) returned the best figures.

There was concern for all-rounder Price when he suffered a hamstring strain and was unable to finish his seventh over.

Price nonetheless opened the batting, with a runner, and proceeded to hit four fours and a six on his way to 24 from 34 balls.

When Price was bowled by Aaron Payne (2-25), the Rosellas were 3-46 but that was the last wicket Charlestown took.

King and Andrews then combined to steady the ship and sealed victory on the last ball of the 30th over.

Having clinched back-to-back Tom Locker Cup titles, Wests will now set their sights on a "double double" by defending their two-day crown.

They are unbeaten in any format this season.

"We're playing some really good cricket this year, especially with the ball," King said.

"I think our bowling attack has been brilliant.

"So we are confident of being there in the [top] four, but as you know anything can happen in a semi-final."