For the second time in three years, the San Francisco Giants will enter spring training with the feeling of being World Series champions. 

However, there are still some questions that need to be answered and some concerns about the defending champions.

Tim Lincecum and Hunter Pence were among the players who struggled last year, and while they both stepped up in the playoffs to help the Giants win the World Series, both have a lot to prove in 2013. While the Giants didn’t make any major offseason moves, they gave out a lot of minor-league deals.

What does that mean? Every player who received one of those miniature contracts has a lot to prove in spring training.

Here are four battles within the team to watch for in 2013.

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