ESSENDON will be without gun defender Adam Saad for at least the next two weeks after scans showed he had suffered a hamstring strain against Port Adelaide.

Saad went off the field with the niggle for assessment but came back onto the ground and played out the game.

After the match, coach John Worsfold said the half-back had been put back into the contest as he hadn't suffered a hamstring injury.

THE RUN HOME Who'll play off for September glory?

However, the club on Tuesday confirmed he will miss at least this week's clash with the Western Bulldogs.

"Adam Saad has a low-grade epimysial strain, which is a sheath around the hamstring," fitness boss Justin Crow said on the club's website.

"Usually you would miss two weeks, but he is actually presenting quite well early on so we will be assessing him over the next couple of weeks about when he's ready to return."

It is a blow for the Bombers, who are fighting for a top-eight spot and have been hit with a raft of injuries to key players in the second half of the season.

Youngster Matt Guelfi adds to that list, with the versatile Bomber to miss the rest of the season after suffering a knee injury at training on Monday. He tore his meniscus and required surgery this week.

FULL INJURY LIST Who's ruled out and who's a test?

Key forward James Stewart has also undergone surgery after battling a debilitating groin injury for most of the season.

Captain Dyson Heppell will need to prove his fitness at training before being cleared to play after missing the past two weeks with a foot injury.

Find In the Game on Apple Podcasts, Google Podcasts or Spotify

Shaun McKernan will return from illness, while Darcy Parish (concussion) and Aaron Francis (neck) will also need to prove their fitness to face the Dogs on Saturday night.

"Darcy was assessed and according to the concussion protocol on match day you're not allowed to return to the game," Crow said.

"He will be following that concussion protocol through this week and our doctors will make a decision about his availability depending on how he progresses.

"Aaron Francis just had some whiplash in the game, we'll be monitoring him through this week."