Borussia Dortmund welcomed back Nuri Sahin to their ranks by firing five past Werder Bremen.
Marco Reus, Mario Goetze, Filipe Santana and Robert Lewandowski had already put the result beyond any doubt before Sahin made his second debut for the club as a substitute, following his loan move from Real Madrid.
The midfielder spent six years as a first-team player for Dortmund before joining Madrid in 2011, but after struggling to break through at the Bernabeu, and following a truncated loan spell at Liverpool, he is back at the club he knows best.
He was on the field when Jakub Blaszczykowski made it 5-0 to Jurgen Klopp's men, who remain in third position, still 12 points adrift of league leaders Bayern Munich.
Sahin began on the bench, and Klopp chose Santana in his defence to replace the injured Neven Subotic.
The rest of his team had a familiar look about it, and Reus' ninth-minute goal for last season's champions was also a familiar sight as he curled in a direct free-kick beyond the reach of Sebastian Mielitz.
Ten minutes later, Gotze made it 2-0 with a shot which took a deflection off Theodor Gebre Selassie after Kevin Grosskreutz set up the Germany international.
Dortmund continued to dominate, with Lewandowski denied by Mielitz before Gotze kept the Bremen goalkeeper warm.
Santana gave Dortmund a comfortable lead early in the second half when he headed in Gotze's corner in a style in which the man he replaced, Subotic, would have been proud.
Bremen coach Thomas Schaaf knew the game was already decided and he gave Ozkan Yildirim his Bundesliga debut in the 54th minute.
The home side started to make a fight of it, but any lingering hopes were dashed in the 81st minute when Lewandowski got his name on the scoresheet with a simple tap-in from Lukasz Piszczek's cross.
Sahin made his entrance in the 84th minute and, a minute later, Blaszczykowski rounded off the scoring with Piszczek again the provider for a simple finish as Dortmund made it look easy at the Weser Stadion.