Western Bulldogs captain Bob Murphy will miss the next three to four weeks of football with a hamstring injury.

Murphy suffered the injury late in his side's win over the Saints at Etihad Stadium on Saturday, after pulling up while trying to tackle St Kilda's Jade Gresham in the centre of the ground.

The Bulldogs have also confirmed the club will use this opportunity to send Murphy under the knife for some minor knee surgery.

“Our assessment over the last 24 hours has confirmed that Bob has a moderate grade hamstring injury,” Bulldogs’ Medical Services Manager Chris Bell told the club's website on Monday.

“We’re also going to use this time while he’s in rehab to perform a quick arthroscopic cleanout on his knee, to address some of the minor signs of wear and tear he’s had.”

Forward Clay Smith will also miss some time due to injury, after he was a late withdrawal from Saturday's game.

Smith injured his calf in the Dogs' final training session on Friday, and will miss the next two weeks with a minor calf strain.