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) after 14:35 in the second term kickstarted the Swans, as they 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 Goulburn Valley export Lachie Shultz (Moama) also kicked a goal, while Cohuna's Josh Treacy pulled out of the match with illness.
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