Neal underwent an appendectomy on December 12, 2011 and was sent to the Austin Toros of the NBDL for a medical rehab assignment on Monday.
But on Monday night, San Antonio's Manu Ginobili suffered a fractured fifth metacarpal in his left hand during a loss to the Timberwolves. The timetable for Ginobili's return has yet to be determined.
As a result, Neal will be thrust back into the lineup and will attempt to duplicate his successful rookie campaign, as he averaged 9.8 points and 2.5 rebounds in 80 games last season.
Diogu played 36 games for the Clippers last season and averaged 5.8 points and 3.2 rebounds per outing. The 6-foot-9 forward has appeared in 223 games throughout his five-year career and logged 6.0 points and 3.1 rebounds. He has also played for the Pacers, Trail Blazers and Kings.