Emerging forward Nate Caddy's career-best six-goal haul wasn't enough for the Bombers in their 16.9 (105) to 14.11 (95) defeat to the Power in the dead rubber at Marvel Stadium.
Sunday's result left wooden spooners Essendon with a 2-21 record for the year, worse than even the 2016 'top-ups' season which generated three wins.
The Bombers also won only two games in the 1933 VFL season, though that was in a shorter 18-round home-and-away campaign.
Interim coach Dean Solomon will hand the reins to a new full-time appointment in the coming days, with Essendon looking to usher in a new era and climb off the bottom of the ladder.
"It's going to take a bit of time and I know that patience isn't a thing that we've all got at the moment due to the last 15-20 years, but we are absolutely on the right path as a football club," Solomon said.
"To see Caddy perform the way he did today and a handful of those other young kids ... I keep saying it, another 40-60 games and it's going to be really exciting.
"It's going to be hard work individually and collectively, and there's no short cuts, but we are on the right path."
That future may not include former captain Zach Merrett, who tallied a game-high 32 disposals and a goal against Port amid speculation he could again attempt to force a trade.
Essendon held Merrett to his contract when he tried to join Hawthorn last year.
"Ultimately that will be his decision and a lot of that will play out over the coming month," Solomon said.
"From a personal point of view I hope he's going to stay and he gets what he deserves at the end of his career."
Caddy shone in attack but Port had their own star at the other end as stand-in captain Mitch Georgiades kicked five goals.
Mitch Zadow and Jack Whitlock added two important goals each in the second half, while Jase Burgoyne (30 touches, two goals) and veteran Ollie Wines (27, one) were also key contributors in a tight game.
The victory gave 15th-placed Port a 7-16 record in Josh Carr's first season as coach since taking over from long-time mentor Ken Hinkley.
"It's been an enjoyable year," Carr said.
"The last five weeks have had challenges and that's predominantly around personnel.
"The silver lining to that is there are guys getting games into them against really good teams and getting feedback on the difference between the two sides.
"Whether the year's a success, I think that's determined by the future."
Port led Essendon by 22 points before half-time but found themselves in a battle when Caddy dragged the home side back into the contest.
The Power scored freely from centre-bounce as a last-quarter shootout unfolded, with the lead changing hands five times for the term.
Merrett looked to have kicked the match-winner when he converted a free kick with less than two minutes left, before Georgiades hit back with a calm set shot and then helped set up the sealer for Whitlock.
Will Setterfield (32 touches) and Archie Roberts (27) were busy for Essendon, as was captain Andrew McGrath (25) in his 200th game.
