The Seymour product kicked a goal at the 15-minute mark of the first quarter as the Dockers started strongly, leading by seven points at quarter-time.
Two of Mundy's teammates kicked goals early in the second and Freo led by 17 points.
But a hanger and goal from Issac Heeney (five goals for the match) kickstarted the Swans, who kicked eight goals in a row to lead by 35 points at the final change after taking the lead late in the second quarter.
Like his team, which lost 8.10 (58) to 14.14 (98), Mundy also performed below his lofty standards.
At half-time, the 36-year-old had eight disposals (four kicks and four handballs), one mark and a clearance.
By the end of the game, Mundy collected 17 possessions, 10 of which were handballs, two marks and three clearances.
Mundy will break the club's games record in the final round of the season if he does not get injured or suspended between now and then.
He will also have a heavy load to carry in the remaining four rounds after star players Nat Fyfe (shoulder) and Michael Walters (hamstring) went down with injuries.
● Fellow Seymour product Josh Schache reinvented himself as a defender and played one of the best games of his career in Western Bulldogs’ top-of-the-table clash against Melbourne.
Schache had 17 touches, 12 of which were kicks, six marks, four tackles, four hitouts and two clearances and spent 95 per cent of the game on the ground.
Schache's performance was even more important after fellow Goulburn Valley export and defender Alex Keath went down with a hamstring injury.
The Bulldogs climbed to the top of the ladder with their 13.7 (85) to 9.11 (65) victory.
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