[12] 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.

[27] 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.

[28][29] 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.

[35] In round 10, against the St George Illawarra Dragons, Croker played in 150th NRL match in Canberra's 32-18 loss at WIN Stadium.

[36][37] In round 13, against the Newcastle Knights, Croker notched a 1000 career points in Canberra's 44-22 win at Hunter Stadium.

After the season ended, Croker was named the Australia Four Nations train-on squad but later dropped out due to a knee injury.

In Round 11 against the Parramatta Eels, Croker played his 200th NRL career match in the Raiders 22-16 win at ANZ Stadium.

In round 18 against the North Queensland Cowboys, Croker suffered a season ending knee injury in the Raiders 38-12 win at Canberra Stadium.

[57] Croker finished the 2018 NRL season with him playing in 17 matches, scoring seven and kicking 63 goals for the Canberra side.

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.

[58] 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.

Croker captained Canberra in the 2019 NRL Grand Final as they were defeated 14-8 by the Sydney Roosters at ANZ Stadium.

[62][63][64] Croker played 22 games for Canberra in the 2020 NRL season as the club finished 5th on the table and qualified for the finals.

[68] 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.

[69] In round 6 of the 2023 NRL season, Croker made his return to the Canberra side in their 20-14 upset victory over Brisbane.