Le Brocq won the 2012 Australian Formula Ford Championship, which led to a contract with Erebus Motorsport's driver academy.

Le Brocq made his debut in the Dunlop Series with Image Racing in a Ford FG Falcon in 2014.

Le Brocq made his debut in the Supercars Championship at the 2015 Sandown 500 alongside Ash Walsh in the No.

Le Brocq made his solo Supercars debut at the 2017 Darwin Triple Crown as a wildcard entry, racing with his Super2 team MW Motorsport in the No.

For the Pirtek Enduro Cup he moved to Nissan Motorsport to drive alongside Todd Kelly in the No.

In 2018, Le Brocq made his debut as a full-time driver in the Supercars Championship with Tekno Autosports in the No.

(key) (Races in bold indicate pole position) (Races in italics indicate fastest lap) 1 Brodie Kostecki 9 Jack Le Brocq 2 Ryan Wood 25 Chaz Mostert 3 Aaron Love 7 James Courtney 4 Cameron Hill 10 Nick Percat 6 Cam Waters 55 Thomas Randle 8 Andre Heimgartner 14 Bryce Fullwood 12 Jaxon Evans 96 Macauley Jones 11 Anton de Pasquale 17 Will Davison 18 Mark Winterbottom 20 David Reynolds 19 Matthew Payne 26 Richie Stanaway 23 Tim Slade 31 James Golding 87 Will Brown 88 Broc Feeney