He will be out for the year, although the team reportedly has a Plan B in place for the first home game on October 30th.
Video of the injury has now surfaced. It appears it came when the Raptor attempted a backflip.
Like a true professional, he finished the sequence and shook a little kid's hand before limping off.
The video:
Grantland's Zach Lowe wrote a great article about the Raptor earlier this week. An excerpt:
"He is easily one of my five favorite mascots in the league, and it's not a stretch to say that over the last half-decade or so of lethargic Raptors basketball, the Raptor was the very best thing going on during game days at Air Canada Centre. The inflatable Raptor - generally portrayed by the same person, as is the case with most mascots - is a legend. Fans never tire of the bit in which he devours a cheerleader, or a security guard. The Raptor is also super-daring in the inflatable costume, even Rollerblading down the arena steps toward the floor in a bulky outfit that includes a 50-pound blower inside. You try doing that."
Some of his greatest hits (via SB Nation):