ALAN Richardson has backed St Kilda's medical department, despite losing star defender Jake Carlisle to a punctured lung sustained while receiving an injection from club doctors.

Carlisle had been battling soreness in his ribs after a big collision with Melbourne forward Jesse Hogan over the weekend, receiving an injection to "deaden the pain" in the area.

However, the procedure left him with a slight puncture to his lung, making him unavailable for St Kilda's clash with Port Adelaide on Saturday afternoon.

It completed a wretched week on the injury front for the Saints, having already lost young forward Josh Battle to a fractured eye socket and his likely replacement Josh Bruce to a broken fibula.

Experienced defender Nathan Brown will also miss the weekend's match with a hamstring injury, sustained during the side's upset win over Melbourne on Sunday.

Bruce suffered the most significant of St Kilda's injuries after he was involved in a nasty collision with a teammate in a marking contest at training on Thursday.

The injury-riddled forward, who has played just three games for the year due to form and fitness issues, is now set to miss the remainder of the season.

Although Carlisle's punctured lung compounded matters for the Saints, Richardson said he had no issue with the way in which his treatment was handled by club doctors.

"There's a little bit of risk with those," Richardson told reporters on Friday.

"It's quite a common procedure. It happens a bit. I've been in a lot of footy clubs and that is the way that injury is dealt with and treated.

"We've got an outstanding group of medicos that do a really good job. There's always a slight risk and obviously that is what has happened."

Richardson described Carlisle's injury as a "really slight puncture", saying he is confident the in-form St Kilda defender will be back to take on Carlton next Friday night.

"We're reasonably confident," Richardson said.

"In fact, I got a message from the doctor this morning. He's going really well, so we'd expect that he'd be really close to being right for the Blues next week."

St Kilda has turned its form around over the last month, with a come-from-behind victory over Gold Coast followed by an upset win over Melbourne in its last two games.

Richardson does not believe the raft of injury issues the team has subsequently dealt with will suck the energy out of his group as it prepares for its clash with Port Adelaide.

"I certainly didn't sense that yesterday," Richardson said.

"We had a meeting after training. The guys are disappointed for 'Brucey', that's the bigger one. He's going to miss the year now.

"He's an incredibly popular person that just gives everything for the footy club. That's not to suggest that's not Jake as well. But given that's just one week, it's certainly not as big a loss.

"We can't play finals, so we're looking to give people opportunities. We obviously need to keep building our own form, the last couple of weeks have been positive and we're looking to build on that.

"We just got pipped against Port the last time we came over, so we're keen to make sure we stay in good form."