The Thistles got out to a quality start thanks to some fantastic lanes on the flanks created by mids John McKenzie and James Lee.

Lee was also vital in limiting the Swans' ability to stretch the midfield and create lanes of their own by battling through contested marks.

The Swans had their chances early with bursts of entries, however the strong winds at Invermay Park had other plans as many a ball went astray.

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That was until East Coast forward Chae Evans managed to put one through and get his side in the major column.

Thistles forward Joshua Matthews came out of the gate firing as well, booting two goals and providing the side a reliable offensive piece in the gusty weather.

On the back end,Thistles Lachlan McFadzean and Lachlan Bremner proved hard goings for any Swans forwards brave enough to get in close to goal.

That didn't stop East Coast half-forward Sam Child from trying his luck, soccering in a stray ball in the goal square during the second quarter.

The Swans' back end proved disruptive as well as the game progressed, upping clearances to make the Thistles' life inside 50 a tough one.

This was headlined by tall full-back Will Stoltenberg, who together with Adam Breen and Shaun Cannon created an almost unstoppable stoppage generating machine.

As the second half rolled on, the Thistles were virtually unable to generate any kind of traction at half-forward, with the side going goalless in the third quarter.

The Swans, on the other hand, had no trouble moving the ball efficiently through the centre, with great ball-handling from ruck Majak Miar as well as James Faulkner and Adam Marland.

The aggression in contests saw an exhausted Old Scotch side gasping for air as the game went on, with a lack of communication clearly keeping the team from piecing together meaningful possessions.

A goal from Evans gave a hungry East Coast side the lead and momentum mid-way through the third.

From there, the Swans were in cruise control as Old Scotch continued to make bad decisions in the midfield which led to either contests or intercepted marks.

The fourth quarter brought with it a glimmer of hope for the Thistles, as a rowdy Matthews broke free of the contest in front of goal to boot his side back into the game.

However, it didn't take long for East Coast to answer back, with Aaron Seen booting two quick majors to have his team back in the lead.

Swans back Andrew Zammit came in clutch in the closing moments of the game, pushing Old Scotch's forwards to the brink.

East Coast will move on to play Old Launcestonians for a shot at the grand final.