The Giants have confirmed that Kelly will miss at least two games because of the injury he suffered in Sunday's surprise loss to Brisbane.

Kelly, one of their most important players, could be out of action for up to four weeks.

But there is some good news, with vice-captain Stephen Coniglio (knee) potentially available for Sunday's massive MCG clash with surging Richmond.

Also, fellow star Lachie Whitfield looks certain to return against the Tigers after four games out with a collarbone injury.

The reigning club champion was supposed to return for the Lions match, but was a late withdrawal.

Ruckman Shane Mumford, another absentee from the Lions loss, could be back as well.

Kelly will definitely miss the games against Richmond and Collingwood.

GWS hope he will be back for either the away game against Port Adelaide or the local derby the following week.

Giants football boss Wayne Campbell told the club website that the gun midfielder has a grade-one calf muscle tear.

"It looks like three weeks, but it could be a week either side of that," Campbell said.

"At this stage he'll miss this weekend and a couple after that."

Touted for much of this season as premiership hopefuls, the Giants have dropped out of the top four to fifth after upset losses to Essendon and Brisbane.

GWS have won only three out of 17 games at the MCG and their most recent game there against the Tigers was the Giants' 2017 preliminary final loss.

Australian Associated Press