In the past Toulon have been criticised for underachieving but they are fighting on two fronts - in the last four in Europe and leading the Top14 - thanks to players who have won international honours with France, England, New Zealand, Australia, South Africa, Wales and Georgia.
"It seems to me that Toulon have brought in the right kind of people this time around," said McCall.
"They have signed players who have been successful in other places but who are still motivated and ambitious.
"That's critical and when you bring together 15-20 very motivated world-class players, then you'll get some success.
"But at the same time we're in good form ourselves and have lots of great players and we're confident we can give them a run for their money.
"We've been on a great journey in this year's campaign. We beat Racing Metro 92 twice, Munster once and then got a great win against Ulster in the quarter-finals."
Saracens will go into the clash without in-form openside Will Fraser, who has been ruled out due to a shoulder injury.
But McCall is confident he has the strength in depth to cope with the loss and Jacques Burger is back in contention following his long-term lay-off with a knee injury.
"It's very unfortunate for Will because he's been instrumental in getting us to this stage," added McCall.
"It's more of a loss to Will than the team, because he would have played. He's been fantastic all season and is a top young-age talent.
"But we have some really good back rows at the club, so we'll be able to accommodate Will's loss. We just feel for him."