According to Kings.com via twitter:

Sacramento Kings
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The Kings today recalled center Hassan Whiteside from the Reno Bighorns of the D-League, as announced by Geoff Petrie.
This isn’t as much a surprise move as it is a disappointing development.  During Whiteside’s 14 games in the NBA D-League, he started only three games and averaged a mere 10.5 minutes per game.  Whiteside played over 15 minutes once in his stint in Reno.  In that game, he scored 12 points on 5-9 shooting, grabbing seven rebounds and blocking eight shots in 29 minutes of play against the Rio Grande Valley Vipers.
Overall, the Kings’ second round pick averaged 4.4 points, 2.7 rebounds and an impressive 2.14 blocks per game.  Whiteside struggled with both fouls and turnovers in the D-League, something the Kings were looking for him to improve on during his stint.  It is doubtful that the Kings expected Whiteside would receive only 10.4 minutes a game from the Reno Bighorns’ head coach, Eric Musselman.  Before he was called up, Whiteside had only played a total of 25 minutes over his previous four games, falling completely out of the rotation in Reno.
The Reno squad is the NBA D-League affiliate of both the Sacramento Kings and the Golden State Warriors, both former employers of Musselman.  The Kings have been reluctant in the past to send their young players down to the D-League, using it only once; a five game stint during the 2008-09 season for then-rookie, Donté Greene.
According to Kings.com, Whiteside will not be joining the parent club during their six game, 11 day road trip.  Instead, Whiteside is going to Sacramento to train at the Kings’ facilities.