PADDY McCartin is close to returning from his third concussion this season, with the St Kilda young gun expected back soon after making "really positive" progress.

McCartin missed the Saints' narrow win over Essendon last round after another head knock against Gold Coast the previous week and has been ruled out of Sunday's clash with Melbourne.

But the 20-year-old former No.1 draft pick remains on track to play football again this season.

"Paddy's been ruled out for this week, but he's progressing well," coach Alan Richardson said.

Veteran Saint unsure whether to go on

"He's training strongly, he's still got a couple of tests, is my understanding, and we'll have much more information early next week.

"But he's looking like he'll come back and play footy shortly.

"For reasons that we've explained a few times now, we've just been a little bit careful, but it's all really positive."

After watching his side narrowly avoid a morale-sapping defeat to the Bombers last round, Richardson forecast several changes for the Demons clash at Etihad Stadium. 

Jack Billings is right in the mix after a stellar comeback from an ankle injury in the VFL, racking up 45 touches and booting two goals in his first game for a month. 

With damaging defender Shane Savage (concussion) all-but ruled out, the door could also swing open for father-son pick Bailey Rice or Brandon White to debut.

"It's unlikely that Savage will play. He was out of the (Bombers) game with concussion, so we're looking for a defender," Richardson said. 

"I would expect there would be a couple of changes – Billings is one that has only had the one game back, whilst he's been able to run and train strongly in his period away from playing we were pleased with the way he played, so he's giving himself a chance. 

"There's a couple of young blokes who haven't played yet in Rice and White that have been going really well for us as well, so there's a few that are in the mix." 

Rice, the son of former Carlton and St Kilda star Dean, was a prized selection for the Saints after choosing them as his preferred destination in last year's draft. 

The 184cm youngster was taken with pick 49, nine spots behind 188cm running backman White. 

The Saints have won four of their last six games and could climb to ninth spot on the ladder with their 14th-straight win over Melbourne this Sunday. 

St Kilda will take in some extra confidence from thumping the Demons by 39 points in round six, despite star Melbourne forward Jesse Hogan booting seven goals. 

"He's a good player, he's had good form against us and if we don’t get pressure on the ball any one of their forwards is going to do some damage – not just Hogan," Richardson said. 

"We know they've been playing some really good footy, some strong footy and the way they move the ball now is a real challenge for teams. 

"The influence of (ruckman Max) Gawn and how effective they are with some quality midfielders is a real handful and they've got some real speed and power in the front half."