Sydney Stack in action during Sunday's loss to Fremantle at Optus Stadium.

Sydney Stack was a major positive for Richmond in yesterday’s narrow Round 20 loss to Fremantle at Perth’s Optus Stadium.

The talented 21-year-old, playing just his fourth AFL game this season, and 30th all-up, starred for the Tigers in defence.

He finished the match with an AFL career-high 25 disposals, career-high five rebound-50s, career-high10 marks, a game-high and career-high 12 intercepts, four score involvements and career-high 455 metres gained.

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Richmond coach Damien Hardwick paid tribute to Stack during his post-game press conference.

“He was very good. He’s built ever since he came back into the side,” Hardwick said.

“We stuck by him as a footy club and Sydney worked incredibly hard to earn the trust of the group again . . .

“He’s been head down, backside up.

“So, look, it is a great sign for him. But the challenges are certainly there moving forward for Sydney once again . . .

07:45

“He’s an incredible football player, there’s no doubt about it.

“What I have been really impressed with is his ability to learn and grow from an off-field perspective, which we think is going to hold him in good stead moving forward.

“He’s only scratching the surface of his career.

“There’s no doubt he can play the game, and we’ll continue to invest in him, both on and off the field.”