No less than six Jacks featured in St Kilda’s win over Essendon last Saturday night.

Each Jack was influential, as Saints fans have come to expect, but there was a time before the name Jack dominated the list’s landscape.

First came Steven, then Newnes, known as Jack and “Jill” respectively for obvious reasons.

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But on this day in 2015, St Kilda’s on-field Jack count doubled.

In a sign of things to come, a young pair of Jacks in “John” Lonie and “Pins” Sinclair ran out for the first time in red, white and black.

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Sinclair started as the substitute against the Giants, forced to wait until the third term to replace Dylan Roberton and make his mark.

The then-20-year-old ended the match with eight disposals, four marks and a clearance in just over a quarter of footy as the Saints went down by nine points in the opening round of the 2015 season.

The debutant almost finished with a major in the final quarter, but his shot on goal in the dying minutes of play only contributed to the Saints’ minor score tally.

Fellow Jack Lonie was quiet on debut with just nine disposals; numbers which on paper don’t indicate a game of significant influence; but his six contested possessions that day tell a more accurate tale.

To this day, Lonie isn’t accustomed to huge numbers; his highest disposal gathering sits at just 22.

Jack Lonie brings down Bombers big man Michael Hurley on Saturday night.

But it’s his trademark unrelenting pressure that leaves the biggest mark, with his overall figures on the stats sheet immeasurable in impact and significance on the game.

Fast-forward to last Saturday night, and the dynamic Sinclair was instrumental in the game’s outcome, amassing nine tackles, five inside-50s and a clutch goal.

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Lonie played a similarly crucial role, laying a game-defining tackle on big man Michael Hurley which perfectly embodied his importance to the Saints’ 22.

Often unsung, the No. 13 was among the best last Saturday, with his 13 disposals, three tackles and five inside-50s the linchpin of his side’s pressure drive.

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The new Jacks didn’t blow the AFL world away in their debut outings, but each has grown so much in the space of just four years.

Last Saturday was a testament to that.

And there will be plenty more displays of that calibre to come.