The Cats have given the green light to Christensen, who had surgery on his back in February, and Josh Caddy, who broke his foot at training in April, to return to the senior side after solid showings in the VFL last week.
The pair will be joined by debutant Shane Kersten, as well as Steve Johnson, Jared Rivers and Hamish McIntosh, who were rested last week.
However, Harry Taylor (knee) and George Horlin-Smith (back) have been ruled out with injury.
He replaces Aaron Hall in the side that lost to West Coast by three points last week.
Other notable round 14 inclusions include Dayne Beams, Dustin Fletcher, Brian Lake and Mike Pyke.
Zak Jones, the Sydney Swans' first-round draft pick from last season, will make his debut in Friday night's duel with Richmond at the MCG.
Jones, the brother of Melbourne captain Nathan Jones, will be joined by Mike Pyke, who returns to the side after being a late withdrawal for last week's classic against Port Adelaide.
Richmond's engine room will be bolstered by the inclusions of Matt Thomas and Reece Conca, although the Tigers lose Chris Newman to a groin complaint.
Port Adelaide midfielder Hamish Hartlett has been ruled out of Saturday's meeting with the Western Bulldogs at Adelaide Oval on Saturday.
Hartlett rolled his ankle against the Swans last week and was unable to prove his fitness for the Dogs game. However, the return of Jared Polec will go some way to mitigating the loss of Hartlett.
Polec has been picked alongside Tom Logan and Sam Gray, while Dom Cassisi (knee) and Jarman Impey (soreness) join Hartlett on the sidelines.
Bulldogs veteran Matthew Boyd replaces the injured Adam Cooney who will miss at least three weeks with a hamstring complaint.
Hawthorn's defence will be bolstered by the return of Lake for its key clash with Collingwood at the MCG on Saturday.
Lake, who has missed five games with a calf injury, will join Jack Gunston, who was a late withdrawal with a corked quad, back in the side.
Ben McEvoy and Ben Stratton have been named to play for Box Hill Hawks in the VFL.
Collingwood has dropped promising ruckman Brodie Grundy for the game against the Hawks, but the Pies have regained Dayne Beams who missed last week with a sore calf.
Essendon has made two changes for its crucial Saturday night encounter with Adelaide at Etihad Stadium.
Key veteran Paul Chapman has been rested, while Jake Carlisle will miss with a knee injury.
Experienced defender Dustin Fletcher makes his way back into the side along with the nippy Travis Colyer.
Adelaide has made one change with Jarryd Lyons replacing the omitted Matt Crouch.
Fremantle midfielder Clancee Pearce has won favour with coach Ross Lyon, returning for his first game since round nine against the Brisbane Lions at Patersons Stadium on Saturday night.
Pearce comes into the Dockers' line-up at the expense of youngster Tom Sheridan.
As flagged this week, Lions key forward Jonathan Brown has been ruled out with concussion. Mitch Golby and James Aish (rested) will also miss.
Friday, June 20
Richmond v Sydney Swans at the MCG, 7.50pm AEST
Richmond
In: M.Thomas, R.Conca
Out: C.Newman (groin), B.Lennon
Sydney Swans
In: M.Pyke, Z.Jones
Out: D.Hannebery (ankle), G.Rohan
New: Zak Jones (Dandenong U18)
Saturday, June 21
Port Adelaide v Western Bulldogs at Adelaide Oval, 1.15pm ACST
Port Adelaide
In: T.Logan, S.Gray, J.Polec
Out: D.Cassisi (knee), H.Hartlett (ankle), J.Impey (soreness)
Western Bulldogs
In: M.Boyd
Out: A.Cooney (hamstring)
Hawthorn v Collingwood at the MCG, 2.10pm AEST
Hawthorn
In: B.Lake, J.Gunston
Out: K.Cheney, T.O'Brien
Collingwood
In: D.Beams
Out: B.Grundy
Gold Coast v Geelong at Metricon Stadium, 4.40pm AEST
Gold Coast
In: J.Martin
Out: A.Hall
Geelong
In: S.Johnson, H.McIntosh, J.Rivers, A.Christensen, J.Caddy, S.Kersten
Out: H.Taylor (knee), D.Simpson (rested), J.Stringer, G.Horlin-Smith (back), B.Hartman, D.Lang
New: Shane Kersten (South Fremantle)
Fremantle v Brisbane Lions at Patersons Stadium, 5.40pm AWST
Fremantle
In: C.Pearce
Out: T.Sheridan
Brisbane Lions
In: D.Merrett, N.Robertson, T.Cutler
Out: J.Brown (concussion), M.Golby, J.Aish (rested)
Essendon v Adelaide at Etihad Stadium, 7.40pm AEST
Essendon
In: T.Colyer, D.Fletcher
Out: P.Chapman (rested), J.Carlisle (knee)
Adelaide
In: J.Lyons
Out: M.Crouch
Sunday, June 22
Greater Western Sydney v Carlton at Spotless Stadium, 1.10pm AEST
Greater Western Sydney
In: A.Kennedy, K.Jaksch, T.Boyd
Out: T.Scully (hamstring), J.Townsend, J.Cameron (ankle)
Carlton
In: M.Jamison, E.Curnow, L.Henderson, B.Johnson
Out: M.Watson, N.Graham, D.Armfield
St Kilda v West Coast at Etihad Stadium, 3.20pm AEST
St Kilda
In: J.Gwilt, T.Milera, S.Savage, D.Minchington
Out: J.Bruce, L.Dunstan (shoulder), J.Saunders, C.Jones
West Coast
In: L.Shuey,
Out: E.Yeo (hand)
Melbourne v North Melbourne at the MCG, 4.40pm AEST
Melbourne
NO CHANGE
North Melbourne
In: B.McKenzie
Out: L.Anthony