Thuram scored twice as Gladbach boosted their Champions League hopes with a convincing 4-1 victory on Sunday, with Florian Neuhaus and Alassane Plea also finding the net.
However, it was Thuram's celebration after his first goal - Gladbach's second - that grabbed the headlines, as the 22-year-old took a knee, seemingly in relation to ongoing civil unrest in the United States following the death of George Floyd while being arrested in Minnesota this week.
Asked for his opinion on the celebration, Gladbach coach Rose gave Thuram his full backing.
"Marcus has made the point. He has set an example against racism that we all support," Rose said.
Rose was not the only one to offer their support, with Real Betis' Marc Bartra sharing an image of Thuram's celebration on his official Twitter account with the caption "#BlackLivesMatter" and "#NoToRacism".
Reflecting on a fine display from his side, which saw the Foals move up to third place, Rose, speaking to the club's official website, added: "We implemented what we set out to do very well.
"Union Berlin fought back and kept going. With the ball we exuded a certain dominance, even if we may have made one or two simple mistakes.
"Nevertheless, we scored four beautiful goals and so I am very happy with the performance and of course with the result."