He won a PDC Challenge Tour in 2023 and was the runner-up at the 2023 WDF Lakeside World Championship.

Landman also qualified for the 2019 BDO World Championship, losing in the first round to Kyle McKinstry 3–2.

Landman qualified for the 2020 BDO World Championship and reached the quarter-finals after beating Dave Parletti 3–2 and Ben Hazel 4–3 before losing to eventual champion Wayne Warren 5–3.

He whitewashed S in the qualifier before defeating Niels Zonneveld 6–5 in a deciding leg, beating Mats Gies in the final 6-3.

Landman competed in the 2023 PDC Challenge Tour series and won event one, defeating Lukas Wenig 5–2 in the final.