In holding his season wrap-up media session Wednesday, Milwaukee Brewers general manager Doug Melvin posed the question himself that represents his biggest challenge for this off-season.

"How do you improve a 96-win club?" Melvin wondered out loud.

Good question.

If you assume free-agent first baseman Prince Fielder no longer will be wearing a Brewers uniform in 2012, the answer is probably: "You can't." But Melvin is determined to field a playoff contender again next season, so there is work to be done.

The good news is that a strong nucleus of players returns for next season. The outfield returns intact, as does the catching corps, closer John Axford and the entire starting rotation.

Having all five starters under contract is rare but due to change after the 2012 season. Zack Greinke, Shaun Marcum and Randy Wolf all are eligible for free agency next winter, leaving Melvin and Co. some decisions to make.

In all likelihood, the Brewers will approach Greinke and Marcum at some point before free agency to gauge their interest in contract extensions.

"We have to sit down and look at the whole layout of the ballclub," said Melvin. "We've done that preliminarily, what we want to do long-term. Starting pitching is a key thing, but we have some other players we might sit down with, too, and talk about long-term deals."

The biggest question for 2012 is the makeup of the infield. Fielder is expected to bolt via free agency, leaving a huge hole in the middle of the lineup. After Fielder and St. Louis first baseman Albert Pujols, the free-agent market for first basemen falls off considerably, with the likes of Carlos Peña, Derrek Lee, Lyle Overbay, Russell Branyan and Eric Hinske.