Originally from Victoria, Sloane was first part of TAC Cup side Eastern Ranges under-18 side when he was only 16, and went on to captain Eastern Ranges in 2008. He was drafted by Adelaide with pick 44 in the 2008 AFL draft.

For the second consecutive year, Sloane was injured in the first game in 2011, against Hawthorn, and was sidelined for several weeks with a fractured jaw and broken thumb. After returning, Sloane played out the remainder of the season, averaging 20 disposals and 5 tackles per game, including a 36-possession game against eventual premiers Geelong in round 21. He continued his emergence as a star midfielder in 2012, averaging 22 possessions and earning three Brownlow votes for best-on-ground in crucial wins over Sydney and Fremantle. Midway through the year, he revealed he had signed a three-year deal with the Crows, saying, “The way Brenton [Sanderson] and the rest of the coaching staff have gone about creating this really enjoyable environment for us to be involved in – I think that’s a big reason why everyone wants to stay around”. Sloane lifted his game yet again in 2013, averaging 23.5 possessions, winning the Malcolm Blight Medal for the best and fairest Crows player, and polling 15 votes in the Brownlow Medal.

Due to the season-ending Achilles injury sustained by captain Nathan van Berlo during pre-season training in 2014, Sloane and Patrick Dangerfield were named as acting co-captains of the Adelaide Football Club for the 2014 season. Sloane continued to thrive in 2014, finishing second in the Malcolm Blight Medal behind Daniel Talia. He played his 100th AFL game in round 23 against St Kilda.

In June 2015, Sloane signed a three-year contract extension with Adelaide, keeping him at the club until 2018. Sloane twice injured his cheekbone during the season, missing a total of five games, but despite that remained one of the club’s elite players, finishing sixth in Adelaide’s best and fairest.

Sloane had an outstanding year in 2016, averaging 25 disposals and leading the club in contested possessions and tackles. He was considered a contender for the Brownlow Medal before being suspended for rough conduct late in the season, rendering him ineligible for the award. Sloane was rewarded with his second Malcolm Blight Medal as the club’s best and fairest player, and was also named vice-captain in the 2016 All-Australian team while being the runner-up in the AFLPA Most Valuable Player award.

In 2019, Sloane was appointed as co-captain of the Adelaide Football Club alongside Taylor Walker.

In 2020, Sloane assumed the sole captaincy and in round one played his 200th AFL game against the Sydney Swans at the Adelaide Oval, which the Crows lost by three points.