The Storm moved four points clear of the third-placed Bulldogs on the back of the 20-14 victory at AAMI Park, with Canberra in the box seat to claim the minor premiership after downing Penrith in golden point earlier on Friday.
Grant has been given a three-week ban, reduced to two weeks with an early plea, for a shoulder charge on Canterbury's Harry Hayes early in the second half, with the hooker sent to the sin bin.
The suspension will likely come as a shock to coach Craig Bellamy, who believed the hit didn't even warrant Grant's temporary stint on the sidelines.
The club has until Monday to decide whether to challenge the grade-two charge, but are unlikely to risk losing one of their leading men for week one of finals.
"In my opinion, I'm not quite sure it deserved a sin bin," Bellamy said post-match.
"It was certainly a penalty, but I thought that a sin bin was harsh, but again, that's just my opinion."
 Melbourne still have two tough top-eight encounters to complete their regular season. They host the Sydney Roosters next Friday night, before a Thursday clash against the Broncos in Brisbane.
But with their points difference 144 better than the Bulldogs, they would need to suffer two monumental losses to lose their top-two spot.
Bellamy said the players, as well as medical staff, would have some input into who gets a rest.
Forward Trent Loiero clocked 48 tackles against the Bulldogs, while fellow State of Origin forward Stefano Utoikamanu has played 21 matches in his first season with Melbourne.
Second-rower Eli Katoa has also been a workhorse, scoring 11 tries in his 22 matches, while the Storm usually take a cautious approach with their thoroughbred winger Xavier Coates, who against Canterbury bagged his 19th try from 18 games.
Cameron Munster has carried a heavy load in recent weeks with his halves partner Hughes sidelined after a shoulder dislocation.
"We have to lose our two games and probably get beat by a fair bit to get out of that top-two position, so we'll have a bit of a sit-down and chat about it," Bellamy said.
"Hopefully, we'll get a chance to rest some players. Some players feel they'd like a rest, then there's others that don't, and sometimes if we're strong that a rest will do them good then we'll sort of force that.
"That's something we'll work out over the next two weeks and take it from there."
Initially forecast to return in week one of the finals, Hughes is confident about being available for the Broncos match as he continues rehabilitation on the shoulder he hurt against the Roosters in late July.
The Storm have only had their first-choice spine on the park for eight matches this season, with fullback Ryan Papenhuyzen also missing a number of games through injury.
"I don't think he needs to play as far as combinations and things like that, but just, I suppose for his confidence, and having confidence in the shoulder," Bellamy said of Hughes.
"I'd hate for him to go into a final with a bit of doubt.
"So if we could take that doubt out of it by playing him in our last round, we'll look to do that, as long as the physios and the medical people think he's 100 per cent right to play."
