Hughes flew back to Melbourne with the rest of the Storm players on Friday after having his dislocated left shoulder put back in place in hospital on Thursday night.
After initial tests in Sydney, the star halfback underwent an MRI in Melbourne before medical staff decided the Kiwi No.7 would not require an immediate operation.
The Storm confirmed he would instead enter into rehabilitation, with the aim of being available for September and hs season not over.
With Hughes to be sidelined until finals, Melbourne's 34-30 win over the Sydney Roosters could prove crucial in their bid to stay in the top four.
The victory momentarily took them to second on the ladder, and ensured Craig Bellamy's men would maintain at least a two-game buffer over fifth spot.
Melbourne play Parramatta next week, before a run home against Brisbane, Penrith, Canterbury, the Roosters and Broncos again.
The Storm will have Cameron Munster back in the halves against the Eels, after his late father Steven's funeral on Friday in Rockhampton.
Fullback Ryan Papenhuyzen is also expected back, after having missed four games with a calf strain.
Melbourne do have options at No.7, but by their own admission Hughes is close to irreplaceable.
Tyran Wishart looms as the most likely option, having filled in at No.6 alongside Hughes at regular intervals in the past 18 months when Munster has been out.
Jonah Pezet is another alternative. Revered as a young talent, the 22-year-old has been battered by knee injuries for the past two seasons.
He has started six of his 12 first-grade games in the halves at the Storm, and is now five matches into his comeback from an ACL rupture and subsequent setback.
"It will be up to them, it will give someone else a chance," Bellamy said.
"Pez is only a young kid, he hasn't had too much first-grade experience at all. He is a good organiser and kicker. We will see what we think is best for the team.
"Mun will come back in and we will go from there.
"But we probably won't recover completely, (Hughes) was the Dally M player last year so that shows how good of a player he is.
"No matter how long he is out for, we're going to miss him."
In other good news for Melbourne on Friday morning, bench prop Tui Kamikamica has avoided a ban for a crusher tackle on Suia Wong.
He can instead escape with a $1000 fine and be cleared to face Parramatta next Thursday night. Â
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