Muscat's men have one hand on the Premier's Plate after a 2-1 win over the Roar in Brisbane on Wednesday.
With two games of the regular A-League season remaining, Victory sit three points clear at the top.
Berisha, the club's marquee signing ahead of the 2014-15 season, finally got to return to Suncorp Stadium on Wednesday.
The Albanian helped the Roar to two championships, and was on the scoresheet for the Victory in their win.
"I think he played the game two or three times in his mind to be honest," Muscat said after the game.
"I felt for him because he's had to wait so long before coming back. He was a little bit on edge the last couple of days but in a positive way.
"Now that he's got that one out of the way I expect him to be better on Saturday."
The Roar, who are seventh but guaranteed a top-six finish due to Perth Glory's salary cap breaches, will be hoping they can get the better of Berisha's Victory on Saturday.
Sydney FC are second and three points behind the league leaders ahead of a trip to Newcastle on Friday.
The Sky Blues will be glad to be away from home, having gone 12 matches without being beaten when on the road this season.
Perth Glory - currently third and appealing the punishments handed down to them by Football Federation Australia - host sixth-placed Melbourne City on Sunday.
Adelaide United and Wellington Phoenix are also in the hunt for a top-two finish.
The Reds visit struggling Western Sydney on Saturday, while the Phoenix should be too good for the Central Coast Mariners a day earlier.
