Atletico Madrid have announced the signing of Axel Witsel on a free transfer following his departure from Borussia Dortmund.

Witsel's BVB contract expired at the end of June after a four-year spell in Dortmund, and he has signed on for a single season at Atletico.

Atletico had reportedly been keen on Boubacar Kamara but are said to have shifted focus to Witsel after the 22-year-old joined Aston Villa.

Hector Herrera's departure to Houston Dynamo meant midfield reinforcements were a necessity for Diego Simeone.

And in 33-year-old Witsel he has added experience and ability, with the Belgium international playing an important role at Dortmund right until his exit.

Witsel made 29 Bundesliga appearances last season as Dortmund finished second to Bayern Munich, though it was long expected he would depart this year.

Simeone will hope Witsel adds much-needed grit to a midfield that was often unconvincing last term, as Atletico's title defence never really got going.

Spain will be the sixth country Witsel has played in during his distinguished career, having previously had spells in his native Belgium, Portugal, Russia, China and Germany.