Geelong gun Jimmy Bartel has joined Steve Johnson on the sidelines and Sydney’s Rhyce Shaw and Ben McGlynn are injured, but Hawthorn regain Jack Gunston.

Hawthorn have suffered an AFL season of woe when it comes to injuries, but have finally caught a break for round 21.

Jack Gunston is shaping for a shock return on Sunday in Perth, where the Hawks tackle Fremantle in a grand final rematch.

Gunston was expected to miss two or three matches with a knee injury suffered in round 19.

But the sharpshooter on Thursday was named in the reigning premiers’ 25-man squad.

Gunston’s timely return for the match of the round comes as fellow forward Jarryd Roughead serves a one-match ban.

The ladder leaders have dropped Billy Hartung, while Brian Lake is back after a four-game suspension.

Veteran defender Luke McPharlin (calf) is out for the Dockers, who have added Michael Walters, Alex Silvagni, Tendai Mzungu and Matt Taberner to their extended squad.

Walters has not played since the Hawks thumped the Dockers in round three, having undergone ankle surgery soon after.

Essendon captain Jobe Watson, Collingwood veteran on-ballers Dane Swan and Luke Ball, Port Adelaide speedster Matt White and North Melbourne star Daniel Wells headline the other notable inclusions for round 21.

Leading premiership contenders Geelong and Sydney both revealed setbacks.

Jimmy Bartel (corked thigh) and Steve Johnson (foot), who collected the Brownlow and Norm Smith medals respectively in 2007, will miss Friday night’s clash with Carlton.

The Blues named an unchanged side, while Billie Smedts and Jed Bews replaced the Cats’ triple-premiership stars.

Sydney will tackle St Kilda on Saturday without Ben McGlynn (calf) and Rhyce Shaw (ankle), with the Swans calling on Shane Biggs and Dean Towers.

Watson, who suffered a rare hip injury in round 12, is one of four Essendon changes for Saturday’s crunch clash with West Coast.

Michael Hibberd, debutant Ariel Steinberg and Patrick Ambrose were the Bombers’ other inclusions.

Utility Jake Carlisle is out due to a back injury, while Simon Tunbridge comes into the Eagles’ side for Xavier Ellis (shoulder).

Collingwood also made four changes for their battle with Brisbane – Ball, Swan, Brodie Grundy and Ben Sinclair all promoted.

Richmond named Ben Lennon in place of Matt Thomas (knee) for Saturday’s game in Adelaide, while the Crows included James Podsiadly and Sam Shaw for Andy Otten (knee) and Tom Lynch (neck).

The Power made one change for Saturday’s game against Gold Coast, fit-again White replacing Kane Mitchell.

Wells has not played since round five due to a foot injury, but is in the Kangaroos’ extended squad for Sunday’s match against the Western Bulldogs.

Mason Wood is a chance of debuting for North, while veteran Daniel Giansiracusa is one of five additions to the Bulldogs’ 25-man squad.

Melbourne recalled co-captain Jack Grimes for Sunday’s clash with GWS, who added ruckman Jonathan Giles to their 25-man squad.