The Tigers' 13.11 (89) to 8.14 (62) win on Saturday evening, combined with Adelaide's loss to West Coast, leaves them a possibility to appear in September after their season looked done six weeks ago.
The Crows' loss leaves the Tigers a game off eighth spot, although Collingwood and Gold Coast could make it two with wins later this round.
The Tigers' past month and a half has set up a massive clash against Essendon on Friday night with both sides in the frame for a top-eight finish.
"It was probably a frustrating game. I thought we moved the ball reasonably well at various stages, we just couldn't quite get that finishing touch inside 50," Hardwick said.
"They've got elite running capacity. They get numbers back and then they charge out so they're going to be a really impressive side.
"We're still not playing to the level that we'd like. We get away with the win today but I thought GWS showed us how good they were going to be."
The Tigers powered away from the Giants in the second quarter; ironically, the same term two of the six MCG light towers plunged into darkness because of an external power problem.
From the 16-minute mark until halftime, play continued in dim lighting as dusk fell around Melbourne and light towers three and five featured one illuminated globe.
By the main break all globes had been restored, but the Giants' hopes of their fifth win for the season had darkened.
After trailing by five points at quarter time, the margin blew to 34 points with Brandon Ellis and Trent Cotchin running rampant through the midfield.
The first quarter had been competitive but largely uncontested – the ball ricocheted from end to end with just 15 tackles laid.
It remained low-scoring with neither side capitalising early on, although Jonathon Patton and Tom Boyd – opposed to Alex Rance and Troy Chaplin – looked dangerous.
However, Rance got the better of Patton as the game wore on and was one of the Tigers' best with 22 touches and 12 marks.
Cotchin exploded out of the blocks for six touches in the first five minutes after starting in the forward line against Josh Hunt.
He ended with 30 disposals, Ellis with 34 and Brett Deledio an impressive 31 with 10 marks.
Five goals to four points in the second term hurt the Giants as their attack off half-back dropped off.
"Our boys probably lost their confidence a little bit and for them to kick five [goals] for the quarter was disappointing," Cameron said.
"But to their credit, I thought our third quarter was terrific and the majority of our last - we just couldn't have that real good connection inside 50 or kick the goals when we needed to."
The Tigers' form would have pleased Hardwick but he would have seen red when Reece Conca had one of the brain fades of the season.
After Devon Smith pulled his jumper over his head, Conca chased the young Giant to the interchange gate and threw a forearm to the back of his head.
Conca was reported as Smith gathered his thoughts on the bench.
The Giants benefitted from the return of Heath Shaw, who had 23 touches despite the attention of Ricky Petterd, while Tomas Bugg did a solid job on Dustin Martin (15 disposals).
Phil Davis was enormous on Jack Riewoldt, who kicked one last-term goal and had limited influence after booting 11 goals against them in round 10.
Adam Treloar and Dylan Shiel kept the Giants in it in the third quarter. They had 14 and 12 disposals respectively as the side kicked the first three goals to inch within 16 points.
But Ellis' opening goal of the fourth quarter and Riewoldt's first of the night a minute later toughened the task yet didn't dampen their spirits.
They didn't let the Tigers claw back some much-needed percentage, which could prove crucial given the logjam beginning to form just outside the top eight.
Tom Scully joined Jeremy Cameron, Stephen Coniglio, Lachie Whitfield, Nick Haynes and Tim Mohr on the sidelines for the rest of the season in the lead up to the game.
The ex-Demon is set for surgery on his knee next week.
Hunt was subbed out in the third quarter with a hip flexor injury and is in doubt for the Giants' clash with North Melbourne next Saturday.
RICHMOND 3.2 8.5 10.10 13.11 (89)
GREATER WESTERN SYDNEY 2.3 2.7 6.10 8.14 (62)
GOALS
Richmond: Petterd 2, Deledio 2, Martin 2, Cotchin, Thomas, Edwards, Griffiths, Ellis, Riewoldt, Houli
Greater Western Sydney: Boyd 2, Patton 2, Hoskin-Elliott, Ward, Treloar, Palmer
BEST
Richmond: Deledio, Ellis, Rance, Petterd, Cotchin, Edwards,
Greater Western Sydney: Ward, Greene, Davis, Treloar, Patton, Kennedy
INJURIES
Richmond: Nil
Greater Western Sydney: Hunt (quad)
SUBSTITUTES
Richmond: Nathan Gordon replaced Sam Lloyd in the third quarter
Greater Western Sydney: Tim Golds replaced Josh Hunt in the third quarter
Reports: Reece Conca (Richmond) for striking Devon Smith (Greater Western Sydney) in the second quarter.
Umpires: Hay, Foot, Mollison
Official crowd: 23,093 at the MCG