Bayer Leverkusen midfielder Gonzalo Castro has not made a decision on his future amid speculation that Borussia Dortmund may trigger his €11 million release clause.
Castro, 27, returned for Leverkusen in their 2-0 victory against Hoffenheim on Saturday following a knee injury sustained in April.
The German midfielder has been at Leverkusen for his entire professional career after coming through the ranks of the club's youth academy.
Castro is under contract at the club until 2016 and has been offered a new deal, but could trigger his release clause until May 25.
He was identified as possible Bayern Munich target in April, but since then has been heavily linked with a switch to Dortmund.
After the match, Castro joined his outgoing teammates Simon Rolfes and Stefan Reinartz on the fence as the club's supporters bid goodbye to their players in their final home game of the season.
Auf dem Zaun sind jetzt #Rolfes, #Reinartz und #Castro. pic.twitter.com/KvKjQbnVuZ
- BILD B. Leverkusen (@BILD_Bayer04) May 16, 2015
However, Castro later played down the celebrations with the fans, and said that his future is still undecided.
"It's all still very, very open," he told Rheinische Post. "I don't have pressure to make a quick decision. Despite my release clause I still have a contract at Leverkusen.
"I know what Leverkusen have offered me, and I have yet to receive an offer from Dortmund.
"In the end, I will decide whether I want to stay or leave. I feel great here, and can also imagine staying here for another season."