Conclusion: 989 Sports made a decision about the direction they were going to bring the MLB series to the PSP and they definitely stuck to their guns with it. They decided to take the already solid gameplay from the PS2 version and leave out a lot of the extras in an attempt at bringing a solid game of baseball that you can play in small, quick doses.
Excerpt: As the old adage goes, “Third time is a charm,” or, in the case of 989’s PSP launch line-up, the fourth time is. MLB is essentially a port of the PS2 version of the same game. With the exception of a few minor details, such as batter walk-ups and celebrations, the presentation makes its way to the PSP relatively intact. Player models are fairly well detailed and animate smoothly. Most of the flashier animations like diving catches and knee catches are around.