The Warriors will wonder what might have been, as they lacked the quality and composure to make the most of several earlier opportunities, but the intensity of their effort couldn't be questioned.
It will give them something to build on, as they look to salvage something from the season.
Fullback Reece Walsh had a strong return, demonstrating his ongoing commitment after the recent dramas, while the pack matched up well against their highly-rated opposites.
The Eels' surgical kicking game was a point of difference, as the Warriors mostly struggled with their fifth-tackle options.
But this display was superior to many others this year and belied their lowly 13th place on the ladder.
Winger Ed Kosi returned for first time since Anzac Day with the Covid-enforced absence of Dallin Watene-Zelezniak, while Chanel Harris-Tavita came into the halves for Ronald Volkman (virus)
Denied any ball from the start, their defensive effort was impressive.
At one point they repelled four consecutive sets on their line and the intensity mirrored what was seen at Mt Smart two weeks before, best shown when five Warriors converged to drive Viliami Penisini over the sideline.
Josh Curran and Harris-Tavita also made impressive close range stops but the Eels pressure eventually told with Waqa Blake's 11th minute try – as the left edge defence got caught out.
That try was a result of pressure, but his second was a gut punch.
The Warriors had territory but Johnson's flat ball was intercepted by Maika Sivo, with Blake finishing off a 90-metre counter. It was a gamble by the halfback, who ran too close to the defensive line.
However, from that setback, the Warriors response was impressive as they stayed in the fight. They dealt with the Eels' direct approach through the middle, then forced a couple of errors.
Their attack lacked polish, but not intent, and the reward came in the 32nd minute, with Marcelo Montoya diving across in the corner, after a clever tip on from Adam Pompey.
The Warriors were up for the contest, shown with Montoya's crunching ribs tackle on Clint Gutherson, which halted a dangerous attack and led the fullback doubled over in pain.
A delightful Walsh skip pass set Kosi free early in the second half, but that opportunity was lost when Tohu Harris made an uncharacteristic error.
Another handling error defused a promising opportunity and Parramatta made them pay, as Isaiah Papali'i came back on the angle to power over from 10 metres, after the marker defenders were drawn in by the dummy half.
In a tight match that felt like a critical moment – and so it proved. Three minutes later Gutherson scored a fortunate try, after Montoya split a towering Moses bomb and the fullback latched on to a desperate pass.
A rampaging Sivo try inflicted further damage before Kosi powered across in the corner moments after Walsh had been held up on the other flank.
A 78th minute Jack Murchie try then added more respectability to a credible defeat.
Eels 28 (Waqa Blake 2, Isaiah Papali'i, Clint Gutherson, Maika Sivo tries; Mitchell Moses 4 cons)
Warriors 18 (Marcelo Montoya, Ed Kosi, Jack Murchie tries; Shaun Johnson 3 cons)
Halftime: 10-6
