I'd like to start this post by talking about Nick Johnson, who the Marlins picked up at the trade deadline this season. In Johnson, the team received perhaps the least athletic-looking major leaguer since the heyday of David Wells. And sadly, that impression was accurate in many ways -- Johnson was slow on the basepaths, practically immobile in the field, and missed numerous games due to injury. But he was still a major part of the Marlins' late-season surge, due to his remarkable ability to get on base. Johnson posted a .477 on-base percentage in his 104 at-bats (plus 36 walks) with the team, and alongside Chris Coghlan, energized the top of the Marlins' lineup.
Sadly, Johnson is a free agent, and is almost certainly gone. This leaves us with a hole at first base -- one which might be filled by Jorge Cantu, if he returns, but if so, who plays third? Will Gaby Hernandez finally get his shot? (Judging by the Marlins' track record, unlikely.) Or is it Logan Morrison's time to make the majors.
Now, here's why I mention Johnson: Morrison looks, at least at this point, to have much the same knack for getting on base. Like Johnson, he's not a huge power hitter, especially for a first baseman -- though then again, he is only 22. But this year, with the AA Jacksonville Suns, he posted a .411 OBP, and walked 63 times while completing only 278 at-bats. (Keep in mind that he did this after missing almost half the season with injuries.) And unlike Johnson, he's reasonably mobile -- he stole 9 bases with the Suns. There's no question he looks like the Marlins' 1B of the future.
But is that future now? That's not so clear. While his on-base percentage in AA was great, he batted only .277, and posted a respectable but not amazing .854 OPS. The Marlins definitely have a history of promoting top prospects directly from AA, but Morrison still hasn't quite dominated at the Southern League level. (Though then again, he was coming off an injury.)
Then again, the team doesn't have a lot of options. They ended the season with only two starting-quality corner infielders, and both Johnson and Cantu might be out the door. I'd expect Hernandez to have a shot to earn the job in camp, but ultimately, the Marlins may end up just turning first base over to the new kid a bit early.
One more note, though: Nick Johnson played AA ball at the age of 20. His on-base percentage for that 1999 season: .525. So let's not get too far ahead of ourselves with Morrison and his .411...