Erich von Manstein during Operation Winter Storm

Generalfeldmarschall Erich von Manstein during the operation to rescue the German 6. Armee that trapped in Stalingrad. Previously, The Red Army launched a huge counteroffensive on 19 November 1942, codenamed Operation Uranus, which was designed to encircle the German armies and trap them in the city of Stalingrad; this goal was accomplished on 23 November. Hitler, aware that if Stalingrad were lost it would likely never be retaken, appointed Manstein as commander of the newly created Army Group Don (Heeresgruppe Don), tasked with mounting a relief operation named Unternehmen Wintergewitter (Operation Winter Storm), to reinforce the German hold on the city. Manstein's initial assessment on 24 November was that the 6th Army, given adequate air support, would be able to hold on.

Source :

"Winter Storm: The Battle for Stalingrad and the Operation to Rescue 6th Army" by Hans Wijers
https://en.wikipedia.org/wiki/Erich_von_Manstein#Battle_of_Stalingrad