In one of the wildest close seasons of free agency in recent memory, Leonard joined up with Paul George to form a formidable pair under Doc Rivers, while Anthony Davis joined LeBron James at the Los Angeles Lakers to create a monster duo of their own, Reuters reported.
With Kevin Durant and Kyrie Irving signing with the Brooklyn Nets – although the former is expected to miss the year with a torn Achilles – it's easy to see how other teams are only becoming stronger by forming blockbuster pairings.
But Nurse said he felt good about his own team and they were setting "super high" goals again this season.
"Predictions don't really factor too much into what you do," Nurse told reporters in Tokyo on Monday ahead of two preseason games against the Houston Rockets.
"We have a lot of confidence in our team, we like the players we have, and I say there's lots of paths to the title. Last year we found one, this year we'll have to find a different one.
"I always think that our objective is to win and win big."
With the departure of Leonard, forward Pascal Siakam is a big part of the Raptors' future following a breakout season in which he was named the NBA's most improved player and was influential in the finals triumph over the Golden State Warriors.
"I think Pascal is going to make another jump. I think he's going to improve immensely," said guard Kyle Lowry.
"His talent is so much, the sky's the limit for Pascal. And for me, my job to help him is to keep him going, put him in good spots to be successful. But sometimes just get out of his way and let him be great," he added with a smile.
With the Raptors in Japan for the week, Lowry was also reminded of the upcoming Tokyo 2020 Olympics and said he'd jump at the chance to play for Team USA.
"If I'm chosen, I'm in. If (USA Basketball managing director) Jerry (Colangelo) and coach Pop (Gregg Popovich) make that call, I'm in. Hopefully I am here and trying to win another gold medal for my country," he said.
"It's an important thing for me to represent my country at the highest level."