A midfielder, 1.86 metres (6 ft 1 in) tall and weighing 83 kilograms (183 lb), Melksham also has the ability to play as a defender, primarily as a half-back flanker.

Growing up in Glenroy, Victoria, he played top-level football early when he joined the Calder Cannons' under 18 side in the TAC Cup at the age of sixteen.

[9] He averaged eighteen disposals during the championships and ranked second overall for Vic Metro in clearances and score assists, behind eventual number one draft pick, Tom Scully.

[13] Furthermore, AFL talent manager, Kevin Sheehan, likened him to St Kilda player and three-time All-Australian, Lenny Hayes.

[19] He was rewarded with the round eight nomination in the AFL Rising Star after he recorded fourteen possessions, three clearances, three tackles and a goal in the twelve point win against St Kilda at Etihad Stadium.

[32] He went on to play every match during the season and was praised for his performances in the midfield by many in the industry, some of which were former player, Garry Lyon,[33] and journalists, Ashley Porter and Martin Blake.

[34][35] In round fifteen, he kicked the match-winning goal in Essendon's four-point win against the previously undefeated Geelong at Etihad Stadium and was named best on ground,[36] earning three Brownlow votes for the first time in his career.

[48] He played the first four matches of the season before he was omitted for the Anzac Day match against Collingwood in round five,[49] he played in the VFL that weekend for Essendon's reserves side in the thirty-five-point win against North Ballarat and was named in the best players,[50] which saw him return to the senior side for the thirty-nine-point win against Greater Western Sydney at Etihad Stadium in round six.

[51] He found himself in trouble when he was reported for rough conduct against Jarryd Roughead during the fifty-six-point loss against Hawthorn at Etihad Stadium in round eighteen,[52] he subsequently received a reprimand from the match review panel.

He was suspended for two years which, with backdating, ended in November 2016; as a result, he served approximately fourteen months of his suspension and missed the entire 2016 season.

[81] After playing all three matches in the JLT Community Series, he made his debut for Melbourne in the thirty point win against St Kilda at Etihad Stadium in round one.

[83] The same weekend, when Melksham was playing for Melbourne's VFL affiliate team, the Casey Demons, he was reported twice and subsequently received a one-match suspension.

[85] He played the remainder of the season in a new position as a defensive forward, and kicked twenty-one goals following his return, with Fox Sports Australia reporter, Brayden May, writing the new role had "breathed new life" into Melksham.

He returned to form in 2020, playing every match of the shortened season, including captaining the side to victory against North Melbourne in Round 11, due to the absence of Max Gawn and Jack Viney.