Mats Hummels, who has been linked with Barcelona and Manchester United, has refused to rule out a move away from Borussia Dortmund this summer.
Reports last summer had suggested that Barca were considering launching a bid for the Germany international after failing to land top target Thiago Silva, who joined Paris Saint-Germain, and just last month, club president Sandro Rosell dropped a huge hint that he was looking to lure Hummels to Spain when the transfer window reopens.
Man Utd have been monitoring the 24-year-old for some time, and it appears a move away from Dortmund could be on the cards.
The centre-back is the latest BVB player to be linked with a move away from the club after it was confirmed Mario Goetze will join Bayern Munich on July 1st.
"I have never made a promise that I will fulfil my contract in the five-and-a-half years I have been here," he told Bild.
While Hummels is unsure whether he will see out his contract at Signal Iduna Park, he hopes striker Robert Lewandowski - also a target for Manchester United - will decide to stay at Dortmund.
"We know that Robert works in this team - he always scores goals here," he added.
"I certainly hope that he stays. For me he is the best striker in Europe this year. When you see his development it is phenomenal."