Mumbai had lost 0-2 and 0-5 earlier in the league this season against Goa.
The visitors will go into the match as clear favorites.
Here is the detailed match preview.
Goa have momentum on their side
In the league table, Goa had finished second ahead of Mumbai.
The visitors are in a positive frame of mind.
They come into this tie after winning three of their previous five matches in ISL.
Goa have built on the philosophy of outscoring their opponents.
The attractive style of play has been the talk of the town. They would want to continue this way.
I don't think we should change our philosophy: Edu Bedia
"I think our philosophy is what has taken us to the top. I don't think we should change this philosophy to approach the play-offs. It has also been the philosophy that has made us the most attractive team this season," said Edu Bedia to Goal.
Mumbai's defense will need to stand up
Mumbai need to be wary of the challenge FC Goa will provide.
Like their opponents, Mumbai have been defensively strong.
They conceded just 20 goals from 18 league matches.
But the defensive structure was breached twice by Goa rather comfortably.
The defenders will need to remain on their toes and prevent Goa from making any sort of inroads.
'We need to focus on what we have to'
Mumbai City defender Lucian Goian said to Sportskeeda, "You have to handle the pressure. We have some experienced players in the team, it's up to us to get the youngsters up to the task. We need to focus on what we have to."
He has netted in 12 goals so far and can create problems for Goa along with Arnold Issoko, who has six assists to his name.
For Goa, Ferran Corominas has been a massive factor. He is the league's top goal-scorer (15).
Central mid-fielder Edu Bedia could have a strong say.
He has scored seven goals.
When and where to watch the match?
The match will begin at 7:30 PM IST on Saturday. The first leg of the semis will be held at Mumbai Football Arena in Andheri. The match will be telecast live on the Star Sports Network. It can be streamed on Hotstar.