Former Germany captain Michael Ballack has dropped his biggest hint yet that he will leave current club Bayer Leverkusen when his contract expires in the summer.

"For the moment, I am not really thinking about extending my contract," the 35-year-old told Sky television ahead of his club's trip to face Kaiserslautern, one of his former teams, this weekend.

"I am playing as if this were my last season at Leverkusen. I still feel good but I don't yet know what I'm going to do.

"If I remain in good health, then I want to carry on for another one, two or three years at a good level. But where that will be, I don't know."

Ballack has made just 25 Bundesliga appearances, scoring once, in an injury-hit second spell with the Factory Team since leaving Chelsea in 2010.

But even if Leverkusen want to keep hold of Ballack, it appears that they will have some convincing to do.

"We need to establish exactly what it is we want to do, what we want to win," Ballack continued.

"Otherwise, we will never improve and we will never finish higher than eighth or ninth."

Leverkusen finished second in the Bundesliga last season, but after losing coach Jupp Heynckes to Bayern Munich, they have struggled for consistency under his replacement Robin Dutt.

With five wins in their opening 12 league games, they currently sit in eighth place in the table, 10 points behind leaders Bayern.