Varnado has been playing with the D-League's Iowa Energy this season and is averaging 14.1 points, 11.0 rebounds and 4.7 blocks.
The Chicago Bulls have been running with just a 12-man roster and under league rules they must add a 13th player on Tuesday. The collective bargaining agreement gives teams two weeks to have a roster under 13 and that expired on Friday. The deadline was extended until Tuesday as the league office was closed for the All-Star Weekend festivities in New Orleans.
UPDATE: According to Adrian Wojnarowski of Yahoo! Sports, the Bulls will fill the 13th roster spot by signing forward Jarvis Varnado to a 10-day contract on Tuesday.