Stuttgart director of sport Horst Heldt is confident out-of-contract striker Cacau will commit his long-term future to the Bundesliga club.
The 28-year-old's current deal expires this summer, meaning he is available on a free transfer should an interested party come forward.
Stuttgart have offered the Germany international fresh terms and Heldt is not panicking despite the striker's delays in putting pen to paper.
"Both sides want to reach an agreement," he told Sport1.de.
"We know what we have got in Cacau and he knows what he has at Stuttgart too.
"We have agreed that a decision will be made in March."
Meanwhile, Heldt insists veteran keeper Jens Lehmann will not remain with the club next season despite his desire to carry on playing.
"We have a clear agreement that his job with Stuttgart ends on June 30, 2010," he continued.
"What happens after then will be decided by Jens and his family - whether he still wants to play football or whether he will hang up his boots.
"I believe that Jens is still really enjoying his football and is still in a top condition.
"He is playing a great season and I am intrigued to see what he will end up doing. I could imagine him taking on a job, for example, in New York.
"But, like I said, I don't know what Jens will do beyond the summer."