In 2013, Hazelwood made his debut in the Australian Formula 3National Championship with R-Tek Motorsport. He raced the full season with the team and finished 2nd in the Championship standings in his rookie season.
Todd Hazelwood started his Development Series career by winning the Shannons Supercar Showdown in 2013 with Supercars team Prodrive Racing Australia. The team helped field a car for Hazelwood to race in the final round of the 2013 Dunlop V8 Supercar Series, with Minda Motorsport. Hazelwood came back in 2014 with Matt Stone Racing driving the iSeek backed Ford FG Falcon. Todd finished 8th overall, and was the highest placed rookie with four top 5 finishes and being awarded the V8 Supercars Mike Kable Young Gun Award. In 2015 Hazelwood returned in the same car with Matt Stone Racing. Todd achieved his very first overall podium at the Sydney 500 and finished 4th overall in the series standings. For 2016 Todd had a few changes over the offseason including changing to a Holden VF Commodore, with a Car of the Future specification chassis. Todd finished in the top 3 four times throughout the season. He finished 3rd in the series and also won the Supercars Privateers Cup for the highest placed team/driver not affiliated with a main series team. In 2017 Hazelwood again drove a VF Holden Commodore from Matt Stone Racing supported by Bigmate. Todd consistently qualified and finished in the top 10 all year long. This included 14 front row starts, 13 podiums and 6 race wins. A total of three pole positions also helped Todd receive the Armor All Pole Position Award. With Todd's dominant and consistent results, Todd won the Dunlop Super2 Series Title by 95 points over Paul Dumbrell.
Hazelwood made his Supercars Championship debut with Matt Stone Racing as a wildcard entry at the 2017 Ipswich SuperSprint, finishing 22nd and 18th. He made his Enduro Cup debut driving with Tim Blanchard at the 2017 Sandown 500, though the car did not start the race after Hazelwood was involved in a major accident during the first qualifying race. The duo finished 12th at the Bathurst 1000 and 15th and 20th at the Gold Coast 600 to finish 22nd in the Enduro Cup.
Matt Stone Racing (2018–19)
Hazelwood made his full-time debut in 2018, moving up with Matt Stone Racing with the team acquiring an ex-DJR Team PenskeFord Falcon FG X. The team and driver struggled with the adjustment, leading to a mid-season switch of chassis to the Holden VF Commodore used in Super2 in 2017 at The Bend SuperSprint. A trying season continued, and Hazelwood finished 26th in the championship with a best race finish of 13th at the Newcastle 500. He and Bryce Fullwood would finish in 20th and two laps down at the Bathurst 1000 after Fullwood spun into the sand-trap at Murrays' Corner on lap 94. Hazelwood continued with Matt Stone Racing in 2019, with the team acquiring an ex-Jamie Whincup Holden ZB Commodore and a technical alliance with Triple Eight Race Engineering. Results immediately improved, with Hazelwood making his first Top 10 Shootout and achieving his first top 10 finish during the second race at the Adelaide 500.Hazelwood achieved a career best finish during the 2019 season, a 5th placing during the Pukekohe round.
