After an injury-affected start to his career that included just 24 AFL matches in his first five seasons, Astbury settled into a fullback and centre-half back role by 2016 and was a regular member of the club's senior side.

[5] Despite migrating fully to the role of key defender that off-season, Astbury was in November 2010 assigned the number 12 guernsey worn by club goal-kicking legend and recently retired forward Matthew Richardson.

[16] In the early parts of the 2012 season Astbury remained ruled out of action, with a second surgery forcing him to prolong rehabilitation on the knee injury sustained the year prior.

[16] For the first time in three years Astbury begun the 2014 season in the club's best-22 and by round 2 had already turned in a "standout" performance, having kept Carlton's Jarrad Waite to just one goal while also recording 10 marks and five rebound-50s of his own.

[33] By the conclusion of round 8 it was clear Astbury was having the best season of his career to-date, a fact later confirmed when the club's best and fairest count revealed he was Richmond's second highest vote polling player to that point of the year.

[34][35] More injury troubles would await him however when in round 9 Astbury suffered another patella dislocation (this time in his left knee) while attempting to tackle Melbourne midfielder Jack Viney in the third quarter of that match.

[45][16] He was relegated to VFL football after a poor performance in round 6 however and faced a hamstring strain in the following weeks that would restrict his ability to push for senior selection.

[51][52] By the middle of October a deal was reported to be almost complete, but a late period decision by Astbury to remain at Richmond saw him still at the club by the close of the trade deadline.

[53][54][55] Astbury underwent minor hip surgery in the lead-up to the 2016 season, but still managed what the Herald Sun labelled a "brilliant" pre-season training campaign.

[70] During the off-season Astbury avoid the contract drama of the year previous, having quietly signed a new three-year deal to keep him at Richmond until the end of the 2019 season.

[24] In round 3 though he was impressive in his own right, restricting reining Coleman Medalist Josh Kennedy[72] For that performance he earned an honourable mention but ultimately went unselected in AFL Media's Team of the Week.

[78] Another starring performance came in round 11 when Astbury restricted North Melbourne's Jarrad Waite to a single goal while recording 20 disposals and an equal team high eight intercepts of his own.

[79] Astbury's assignment on Waite was part of a concerted effort by coach Damien Hardwick to have him defend other teams' best key-forwards and allow Alex Rance to play a more fluid offensive role.

[86] In the 2017 AFL Grand Final Astbury was given the task of restricting Adelaide's Taylor Walker, which he did by keeping the Crows captain goalless until late in the match when the game was already out of reach.

[89] Astbury underwent minor shoulder surgery immediately following the end of the 2017 finals series, though still managed to complete a mostly-full training program in the lead-in to the 2018 season.

[95][96] Astbury repeated the accolade in round 4, earning another Team of the Week selection as well as three votes in the AFL Coaches Association's award for his 20 disposal and six mark game against the Brisbane Lions.

[110] Two weeks later he was lauded by the ABC and received four Coaches Association Award votes after posting a season-best 21 disposals and a match-high 11 intercepts in Richmond's round 19 win over Collingwood.

[16][117] He was the subject of significant media attention in the lead-up to the preliminary final two weeks later, after reports emerged that he contracted the common cold and was admitted to hospital for an intravenous drip just two days before that match.

[118] He was ultimately ruled fit to play in that match against Collingwood and did so primarily in defence with a later stint in the forward line when Richmond faced a significant half time scoring deficit.

[127][128][129][130][131] The defence struggled under the task in early weeks, conceding 36 goals over a two-week stretch before stabilising with a win over Port Adelaide in round 4 in which Astbury contributed eight marks.

[145][131] In round 17, Astbury received one vote in the coaches association player of the year award as Richmond's equal fourth-best afield in a win over Greater Western Sydney.

[151] Astbury's addition, along with the suspension of Geelong forward Tom Hawkins provided a key difference, with Richmond winning through to a grand final match up against Greater Western Sydney.

[161][162][163] The match was played under extraordinary conditions, the first of what had been announced would be a shortened 17-round season imposed on the league as a result of the rapid progression of the coronavirus pandemic into Australia.

[175][176] Astbury moved to the Gold Coast with the main playing group to rehabilitate the injury in early-July, relocating due to a virus outbreak in Melbourne.

[177] Astbury progressed ahead of schedule during July and was named by coach Damien Hardwick as likely to return for the club's round 8 match, before complications that week forced him into a slower recovery.

[188] The loss would drive Richmond to structural change however, with Astbury assuming the role of relief ruck in the club's follow-up semi-final win over St Kilda.

[225][191] Astbury was an important but under-recognised part of Richmond's defensive unit during its premiership run in the late 2010s, alongside All-Australians Alex Rance and Dylan Grimes.

[226] Astbury's ability to negate opposition tall-forwards was cited retrospectively as an important factor in allowing Rance and Grimes to play their lauded roles as interceptors.

[214][227] Notes Team Junior Astbury's mother Kate was an unsuccessful candidate for Labor party pre-selection for the Victorian electoral seat of Ripon in 2017.

[228][229][6] Astbury traveled to Rio de Janeiro in the summer before the 2014 season, one of nine Richmond players making a cultural-exchange trip as part of a project to work with disadvantaged kids that was developed by researchers at the Royal Melbourne Institute of Technology.