The European champions made an incredibly positive start to the 2017-18 campaign as they picked up a 55-24 bonus-point triumph over Northampton.
Saracens ran home nine tries with Sean Maitland scoring a hat-trick, while Brad Barritt, Richard Wigglesworth, Alex Lozowski, Vincent Koch, Schalk Brits and Ben Spencer also got in on the act.
McCall admitted that there is still room for improvement from last year's play-off semi-finalists but was pleased with the overall performance at Twickenham.
"It was a really good overall team performance," McCall told the club's official website.
"We won a lot of collisions, the way we carried the ball, the way we cleaned, got a lot of quick ball out, scored some good tries.
"There are some things for us to clearly work on, but overall a really positive start to the season."