He played for the New South Wales Schoolboys and Australian Schoolboys representative teams in 2007 before being selected for the New South Wales under-18s in 2008. Croker was part of the Canberra team that won the inaugural
National Youth Competition in 2008. He played at centre and was involved in the try that won the Raiders the match 28-24 in golden point extra time.
2009 Croker broke into Canberra's first-grade side in 2009, making his debut in round 2 against the
Sydney Roosters. In round 3, against the
Parramatta Eels, Croker scored his first NRL try in the Raiders 16-18 loss at
Parramatta Stadium. He went on to make 21 appearances in his rookie season, and was the Raiders highest try scorer with 12 tries. On 3 September, Croker re-signed with the Raiders to the end of the 2012 season.
2010 Croker was again a regular in Canberra's 2010 side, making 25 appearances as Canberra finished 7th and made the NRL finals. However, it was a missed penalty goal from Croker that ended the Raiders' season. In a sudden-death finals match against the
Wests Tigers, in front of a home crowd of 26,476, he pushed wide a 30-metre kick that would have tied the match at 26-26. Canberra's coach
David Furner—himself a former Raiders goalkicker—defended Croker, arguing his goalkicking form had won a number of matches for the team during the season. Days later, Croker was selected for
Australia's train-on squad for the
Four Nations tournament. Croker played in all of Canberra's 26 matches and was the club's highest point scorer with 5 tries and 53 goals.
2011 On 6 August, Croker re-signed with the capital club until the end of the 2013 season. He finished the
season as Canberra's highest point scorer with nine tries and 53 goals in 23 matches.
2012 in 2012 Croker was the NRL's leading points scorer in 2012 with a total of 226 points, scoring 16 tries and kicking 81 goals in 25 matches.
2013 In round 5, against the Sydney Roosters, Croker played his 100th NRL match in Canberra's 24-22 win, kicking the winning goal after scoring a try in the final minutes of the match at
Canberra Stadium. On 13 April, he re-signed with the Canberra club to the end of the 2015 season. In round 25, against the
New Zealand Warriors, Croker scored his first hat-trick of tries and also scored all of the club's points in the Canberra clubs 50-16 loss at
Mt Smart Stadium. He finished the
season as Canberra's highest point with nine tries and 52 goals.
2014 In February, Croker played in the Raiders
Auckland Nines team. In round 24, against the
Cronulla-Sutherland Sharks, Croker surpassed club legend
Mal Meninga's 864 club career points, taking him to third highest point scorer for Canberra. He finished the
year as the highest point scorer and try scorer for the Canberra side, scoring 18 tries and scoring 202 points. On 5 September, Croker re-signed with the Raiders until the end of the 2018 season. He was named as the 2014 Meninga Medallist for Raiders' best and fairest player. On 12 October, Croker played for the
Prime Minister's XIII team against
Papua New Guinea, filling in for Raiders teammate
Jack Wighton on the interchange bench after he was a late scratching. On 19 December, Croker was named by coach Ricky Stuart as the new captain for the Canberra Raiders following the departure of
Terry Campese to
Hull Kingston Rovers in the
Super League.
2015 In the pre-season, Croker was captain of the Raiders
Auckland Nines squad. On 13 February 2015, Croker played at centre for
NRL All Stars against the
Indigenous All Stars, kicking a goal in the 20-6 loss at
Robina Stadium. On 3 May 2015, Croker played for
Country Origin against
City Origin, scoring a try in the 34-22 win at
Wagga Wagga. In round 10, against the
St George Illawarra Dragons, Croker played in 150th NRL match in Canberra's 32-18 loss at
WIN Stadium. In round 13, against the
Newcastle Knights, Croker notched a 1000 career points in Canberra's 44-22 win at
Hunter Stadium. At the end of the season, Croker was the NRL's top point scorer with 236 points. On 26 September, Croker played for the Prime Minister's XIII against Papua New Guinea.
2016 In February 2016, Croker was named in the Raiders
2016 NRL Auckland Nines squad. On 13 February 2016, Croker played for the
World All Stars against the
Indigenous All Stars, playing at centre in the 12-8 win at
Suncorp Stadium. On 8 May 2016, Croker again represented Country Origin against City Origin, kicking five goals in the 44-30 loss in
Tamworth. In round 10 against the
St. George Illawarra Dragons, Croker became the highest ever point scorer for Canberra in the 16-12 golden point loss at
Jubilee Oval. At the end of the season, Croker picked up the Provan Summons award as well as Dally M Captain of the Year and season's leading point scorer in a year were the capital club fell one game short of the Grand Final. Croker played in all of the Canberra clubs 27 matches, scoring 18 tries and kicking 112 goals in the
2016 NRL season. After the season ended, Croker was named the
Australia Four Nations train-on squad but later dropped out due to a knee injury.
2017 On 10 February 2017, Croker played for the
World All Stars against the
Indigenous All Stars in the
2017 All Stars match, playing at centre in the 34-8 loss at
Hunter Stadium. In round 5 against the
Parramatta Eels in the 30-18 win at
Canberra Stadium, Croker became the third player to score 100 tries for Canberra, after
Jason Croker and
Brett Mullins, and the fifth player to score 100 tries and kick 500 goals in Australian first grade rugby league. He also became only the seventh player after
Terry Lamb (
Canterbury-Bankstown),
Greg Alexander (
Penrith),
Ryan Girdler (Penrith),
Hazem El Masri (Canterbury-Bankstown),
Darren Lockyer (
Brisbane) and
Luke Burt (
Parramatta) to score 100 tries and over 1,000 points for a single club. In Round 11 against the
Parramatta Eels, Croker played his 200th NRL career match in the Raiders 22-16 win at
ANZ Stadium. On 10 August 2017, Croker extended his contract with the capital club to the end of the 2020 season. Croker finished the
2017 NRL season with him scoring nine tries and kicking 77 goals for Canberra.
2018 In round 18 against the
North Queensland Cowboys, Croker suffered a season ending knee injury in the Raiders 38-12 win at
Canberra Stadium. Croker finished the
2018 NRL season with him playing in 17 matches, scoring seven and kicking 63 goals for the Canberra side.
2019 On 13 February 2019, after being the solo captain for the Canberra club for the past four years, coach Ricky Stuart appointed hooker
Josh Hodgson as co-captain alongside Croker for the season. Croker made his return from injury in round 1 against the
Gold Coast Titans, kicking four goals in the 21-0 win at
Robina Stadium. In round 17 against St. George, Croker became Canberra's all-time leading try scorer with 120 tries surpassing
Jason Croker in a 36-14 victory at
WIN Stadium. In round 22 against Melbourne, Croker scored two tries as Canberra came from 18-0 down at halftime to win the match 22-18 at
AAMI Park. It was the first time since 2015 that Melbourne had lost two games in a row at their home stadium. Canberra finished the 2019 regular season in 4th place on the table and qualified for the finals. The club would then go on to qualify for their first grand final in 25 years. Croker captained Canberra in the
2019 NRL Grand Final as they were defeated 14-8 by the
Sydney Roosters at
ANZ Stadium.
2020 Croker played 22 games for Canberra in the
2020 NRL season as the club finished 5th on the table and qualified for the finals. Croker played in all three finals matches including the preliminary final loss to Melbourne.
2021 Croker was limited to only 12 appearances for Canberra in the
2021 NRL season due to injury and poor form. Despite this, he still managed to be the club's top point scorer for the year. Canberra would finish the campaign in 10th place on the table and miss out on the finals.
2022 After being left out of the Canberra side for the opening eight rounds, Croker made his return in round 9 of the
2022 NRL season against Canterbury. Croker was taken from the field towards the end of the match with a shoulder injury during the clubs 14-4 victory. On 9 June, Croker was ruled out for the rest of the
2022 NRL season after aggravating his shoulder injury in a freak accident at home.
2023 In round 6 of the
2023 NRL season, Croker made his return to the Canberra side in their 20-14 upset victory over Brisbane. In round 15, Croker made his 300th first grade appearance in Canberra's 36-14 loss against the New Zealand Warriors. On 13 August, Croker announced he would retire at the end of the season. Croker's last game was Canberra's 18-29 loss to the
Brisbane Broncos in round 26, in which he played just three minutes. == Post playing ==