The Raptors have been without center Jonas Valanciunas since November 20th .
Backup Bismack Biyombo has manned the middle well and is coming off an 18 rebound , 7 block game .
The Raptors have been without center Jonas Valanciunas since November 20th , but backup Bismack Biyombo has manned the middle well and is coming off an 18 rebound , 7 block game .