The 41-year-old has not been seen on the training track this week after being unsuccessful in his application for the senior coaching role at the club.
After Luke Beveridge was appointed as senior coach, AFL.com.au understands Montgomery wanted to spend a week away from the club to consider his options.
It is the second time Montgomery has been overlooked for a senior job after applying for the Port Adelaide role in 2010 after three years as an assistant at Carlton.
Popular with the players and connected closely to the club’s hierarchy, Montgomery has not made any secret of his ambitions to be a senior coach. He has been at the Bulldogs since 2011.
Despite being overlooked for the top job, the Bulldogs are understood to regard him highly and want him to stay.
Beveridge indicated on 3AW last Friday he sympathised with Montgomery's position and understood he would be disappointed, but that as the new coach he wanted to work with all existing football department staff including Montgomery.
"We'll work out a way forward. I've said all along that no matter what, I am looking forward to working with all of them [football department staff] and that includes ‘Monty’,” Beveridge said.
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Beveridge has worked at Collingwood and Hawthorn and has a reputation for being a fair and open communicator.
The Bulldogs announced Beveridge would be their new coach last Friday after an exhaustive process that saw the club interview several candidates, including Montgomery.
Beveridge was appointed nearly two weeks after the first-to-fourth year players returned to training, with existing football staff having to develop a program without a senior coach in place.
Beveridge, 44, took training for the first time at the Whitten Oval on Monday as the senior players returned to the club.
A decision on the Bulldogs captaincy is expected soon, with Robert Murphy considered the frontrunner.