Musil opened the scoring on a power play in the first period before Saskatoon replied with three straight goals.
Evan Polei brought the game within one early in the third for the Rebels (13-11-4) and Austin Pratt tied it less than four minutes later.
Wyatt Sloboshan, Jackson Caller and Gage Ramsay scored for the Blades (10-16-2).
Lasse Petersen made 21 saves in the victory. Brock Hamm turned aside 31 shots in the losing effort.
The Blades continue their road trip on Friday when they head to Edmonton to take on the Oil Kings.
In other WHL action involving Saskatchewan teams, Giorgio Estephan scored two goals and set up another as the Lethbridge Hurricanes toppled the Prince Albert Raiders 5-1 for their fifth straight win.
Ryan Lindgren, Calen Addison and Tyler Wong also scored for Lethbridge (12-11-3).
Sean Montgomery scored shorthanded for the Raiders (5-20-1), who are winless in their last nine games.
With files from The Canadian Press
© 2016 The Canadian Press