The winger felt the visitors' consolation was unnecessary, but nevertheless praised his heavily-rotated team for the victory.
Mario Gomez proved crucial with his two goals as Javi Martinez and the Dutch winger himself got in on the act as well, but the Netherlands international claimed the goal conceded to their 10-man visitors was unnecessary.
"After going 4-0 up we weren't as focused and we eased off by a couple of percent," the 29-year-old lamented. "You can always let in a goal in those circumstances, but it's a shame, especially for Manuel Neuer, who obviously wants to keep clean sheets.
"A score of 6-1 sounds easy, but it's obviously not if you come into a game like this without match practice. There were six new players on the field, so huge credit to all of them.
"It was important to win again today and maintain our rhythm."
The likes of Xherdan Shaqiri, Diego Contento and Jerome Boateng found their way into die Roten's line-up, as Jupp Heynckes opted to rotate his squad after the 3-1 triumph over Arsenal on Tuesday night.