Borussia Dortmund's first-team players returned to training on Tuesday, although Mario Götze and Raphael Guerreiro were notable absentees.
Götze was not present at the Helmut-Körnig-Halle in south Dortmund due to an illness, while the muscular problems that ruled Guerreiro out of the end of the Hinrunde meant he had to train individually.
The remainder of Dortmund's first-team squad were put through their paces with a fitness test on the running track, before undergoing individual blood tests to determine the levels of lactic acid in their muscles.
On Thursday, 5 January, Dortmund depart for an eight-day training camp in Marbella, Spain, where Thomas Tuchel's side will face PSV Eindhoven and RC Standard de Liege in friendlies. When back in Germany, BVB visit SC Paderborn 07 in a friendly on 17 January, before meeting SV Werder Bremen on Matchday 17.
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