plan to play the first two years and then take on a coaching role for the third year. Cahill made his debut in the FFA Cup on 24 August as a 64th-minute substitute against Brisbane Strikers. In his second game for Melbourne City, he scored and got an assist in a 4–1 win in the FFA Cup quarter final against Western Sydney Wanderers. Cahill made his A-League debut in a Melbourne Derby against Melbourne Victory on 15 October. He opened the scoring with a spectacular volley into the top corner from 35 metres out after 27 minutes. City won the match 4–1. On 30 November, Cahill scored a trademark header in the FFA Cup Final. The victory over Sydney FC was the club's first piece of silverware. On 4 February 2017, just as he was preparing to come on as a substitute against Melbourne Victory FC, Cahill was sent off for using "insulting, offensive, abusive language towards a match official" after he angrily disputed a goal with Chris Beath. This is the first time in Australian football history in which a player was sent off before entering the field of play. On 6 December 2017, Cahill left Melbourne City after not getting enough game time, in a bid for more game time at club level to boost his chances to get selected for the Australian squad for the 2018 FIFA World Cup. Return to Millwall On 29 January 2018, Cahill rejoined his first professional club, Millwall, signing until the end of the 2017–18 EFL Championship season. A week after his return, he played for Millwall's under-23 team in the Professional Development League scoring a goal in their 3–2 victory over Coventry City. The following week, Cahill made his second Millwall debut, coming on in the 90th minute to a standing ovation. He was released by Millwall at the end of the 2017–18 season. Cahill’s ten appearances during this spell meant he retired having played one more league game for Millwall than Everton. Jamshedpur FC On 1 September 2018, Cahill signed with Indian Super League club Jamshedpur. However, he could not make his debut in the first game of the season against Mumbai City FC due to suspension in the game. He made his debut for the club in the next match, a 2–2 draw against Bengaluru. He scored his first goal for the club in a draw with Kerala Blasters,