SYDNEY superstar Lance Franklin will miss the next three to four matches, due to bone bruising in his leg sustained in a clash with Greater Western Sydney defender Connor Idun.

The incident occurred in the third quarter of the Swans' two-point loss to the Giants, but Franklin was able to play out the game and ended the match with five goals in a best-on-ground performance.

Franklin pulled up reasonably well after the match, but the pain and swelling that has flared since the game forced the gun forward to get scans that confirmed the worst.

"Initially it really hurt and then the adrenaline and what happens in the course of a game makes it very hard to diagnose," John Longmire told reporters on Monday.

"It was only yesterday [Sunday] that it got sore.

"[Franklin] reckons he'll be two [weeks], but we've said three to four, which probably gives you an idea of where the discussions go."

Franklin was sidelined for all of the 2020 season and all but 10 games of 2019 due to a series of soft tissue injuries, but has returned this year to play three games and kick 11 goals.

The Swans have reported that Franklin is in good spirits despite the latest setback striking just as he was rediscovering his best form.

"He's all right, this is what happens in football," Longmire said.

"He comes back and unfortunately it was just a collision-type injury that you can't do much about. That's what happens."

Hayden McLean is likely to come back into the team, after playing in rounds one and three when Franklin was still recovering from a calf strain and then rested.

The 197cm forward-ruckman kicked three goals in the Swans' round one VFL victory over the Giants on Saturday.

In a double blow for the Swans, ruckman Tom Hickey will miss the next six to eight weeks after injuring his posterior cruciate ligament in a ruck contest against the Giants.

"There was a two-minute period just before three-quarter time, where we lost both of them within 30 seconds," Longmire said.

Hickey was noticeable by his absence in the final term, as the Giants got on top in the midfield and won the contested possessions for the quarter 39-28 to help them claim a thrilling two-point victory.

With the veteran ruckman subbed out of the game, Sam Reid took a ruck contest for the Swans at the top of the Giants' goal square in the dying moments, but wasn't able to clear the ball far enough away and Josh Kelly swooped on the crumbs to kick the match-winning goal.

Callum Sinclair looms as the obvious replacement for Hickey, especially after collecting 17 disposals and 34 hitouts in the VFL clash with the Giants.

In better news for the Swans, midfielder James Rowbottom is set to return after recovering from a knee issue picked up in round one against Brisbane, and getting through a full game in the reserves.

Rowbottom gathered 23 touches and laid seven tackles in the 26-point victory over the VFL Giants.

"He'll come back in. He's a good player," Longmire said.

"We felt he needed another run on the weekend, and he got through that pretty well. He's pulled up pretty good from that.

"He's an important player for us, he puts some pressure on the opposition, so we'll bring him back in."