Ballack's contract ends in June and the Germany captain is uncertain whether he will be offered a new deal.
The midfielder has not reproduced the form with Chelsea that he showed for Bayer Leverkusen and Bayern Munich and former national team skipper Matthaus fears the worst for Ballack.
Flop? Michael Ballack's Chelsea contribution has been brought into question
'At Chelsea Ballack is just present rather than right in the thick of things. He is a nominal player at the big London club - that is not an insult.,' said Matthaus (left).
'The Chelsea squad is packed with top stars. To establish yourself as a leading player there is hard. Ballack has not managed it.
'He is always in the first team. The question is: For how much longer?'
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