Morton joined the Swans for the 2012 season after four years with Richmond and three years with West Coast, seemingly on his last chance to make it in the AFL, and is on the way to becoming another chapter in Sydney's impressive history of recycling players.
The Western Australian was the dominant goal-kicker for Sydney's reserves side in the North East Australian Football League this year, booting 78 goals, but did not earn a spot in Longmire's senior team until he proved he could meet the standards required of a modern forward.
"He's worked on fitting in with our forward structure and worked really hard at his game and ... I thought last week he had seven or eight tackles which really helped him to be able to be named in our team for this week," Longmire said on Friday.
"He's been able to get that part of his game right over the course of the year and contribute and do a really good job.
"We know he's got some talent but it's about a lot of other different things.
"He's been able to work on that and improve it during the year."
Morton made his debut for Sydney in their 82-point thumping of the Western Bulldogs in Round 21 and has played three of the Swans' four games since then, including both finals.
While the 186-centimetre forward has chipped in with three goals in his four games, it is his 2.8 tackles per match that is clearly a bigger feather in his cap by Swans' standards, considering it puts him alongside Lewis Jetta and Adam Goodes.
In fact, every one of Morton's 11 tackles have come in the finals, putting him behind only Ryan O'Keefe and Josh Kennedy at Sydney over those two matches and Goodes has been impressed by his team-mate's dedication in order to break into the team.
"When you think about any player that comes from a different club, and obviously Mitch has come through other different clubs as well, he had to come and adjust to our game plan and our game style and what we expected of him," Goodes said.
"In the reserves he kicked a lot of goals, which was fantastic, but there were things he needed to work on if he wanted to play senior football for us and that was what Horse (Longmire) was talking about; the one percenters, the tackles, the forward pressure.
"Once he got that right and really he bought into that, the goals were still coming and he was putting on fantastic pressure like he did last week."
Saturday's grand final will be Morton's 76th game of senior football since he was drafted before the 2005 season by West Coast.
Morton played 12 games for the Eagles and kicked 11 goals, while he managed 59 matches with Richmond and booted 94 majors before his move north.
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