COLLINGWOOD could turn to 'Mr Fix It' Tyson Goldsack to plug a gaping hole in defence against Richmond twin towers Tom Lynch and Jack Riewoldt on Friday night.

The Magpies' backline woes were exacerbated on Monday with the news that mid-sized defender Tom Langdon won't play again this year after undergoing surgery last week on his troublesome knee.

The skeleton Pies' defence was made to look "vulnerable" against Greater Western Sydney on Saturday, conceding 19 goals in their highest score against since 2016.

Giants Jeremy Cameron, Harry Himmelberg and Jeremy Finlayson were supported by ruckmen Shane Mumford and Dawson Simpson, exposing the Pies' decision to pick one key defender.

Magpies coach Nathan Buckley against the Giants. Picture: AFL Photos

It could see the Pies select Goldsack for his first game of 2019 after switching from attack to defence in the VFL in recent weeks.

The 32-year-old, who miraculously returned from an ACL in less than 25 weeks to play finals last year, sat out part of the final term in the Pies' VFL win over Frankston on Sunday.

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He then took part in the Pies' AFL recovery session at Olympic Park Oval on Monday with Chris Mayne a notable absentee.

Defender Jeremy Howe, one of a number of Pies forced to play above their height against the Giants, flagged selection changes ahead of Friday's blockbuster.

"Probably on the weekend was a bit of an outlier, we didn't expect them (GWS) to go quite so tall," Howe said on Monday.

"(We) probably expected their ruckmen to play 50-50 off the bench and for them to be able to play forward probably made us look a little bit undersized and vulnerable at times.

"We've played undersized multiple times and managed to get the job done but unfortunately we lost a few key contests which ended up in goals.

"We'll have a look at selection this week but we've got guys putting their hands up so it's a good spot (to be in)." - Jeremy Howe

Lynch and Riewoldt, who are 4-1 in their five matches together this season, combined for six majors against Port Adelaide on Saturday.

Defenders Matt Scharenberg (191cm) and Jack Madgen (192cm) will join Tyson Goldsack (193cm) in contention to tackle the Tigers.

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Ruckman Brodie Grundy was spotted with compression on his left calf during the light jog but is expected to play on Friday.

Mayne was sent for scans on Monday after finishing the loss to Giants with ice on his left knee but was cleared of any serious damage and is expected to train in Wednesday's main session.

Forward Jamie Elliott ran strongly on Monday after missing the trip to Sydney with soreness and will press his case for a recall on Wednesday along with Josh Thomas (hip).

Stopper Levi Greenwood appears a long shot to renew acquaintances with Tiger Dustin Martin after he enjoyed a light running session with fellow hamstrung Pie Darcy Moore on Monday morning.

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Meanwhile, Howe backed Cox to continue to provide an option in attack after he was held goalless from four disposals against the Giants.

"He definitely tips in, he tries as hard as he can but at times you're going to get pushed around and off the ball," Howe said.

"Ideally, you'd love to see him get a run and jump at it, but given teams are going to try and work him under the ball, it's just part and parcel of being a key forward.

"He'll learn, he's got to work on his craft like any other week, but we're not expecting him to come out and do a prelim performance, that's for sure.

"For him to create contests, that's what we expect."