Well I'm sure 99.8% of you people on this site haven't played this, so here's a review, if you're thinking about this.

User Rating: 9 | Jikkyou Powerful Pro Yakyuu Portable 4 PSP
Well, where to start... This is one of my favorite PSP Games, and it's in Japanese. And I don't even find it hard to understand, and let it be noted I speak no Japanese. With this game in hand I am usually never bored. A great overall game.

Gameplay:
If you've played MLB Power Pros, or MLB Power Pros 2008, you'll know what you're doing. Same mechanics, same... everything. Except of course the language.

Language Barrier:
There actually isn't much of one. It takes a little while to figure out what everything means, but once you do you can pick it out.

Graphics:
Toned down from the MLB '08 version. But decent for the PSP.

Game Modes:
Exhibition: Of course there's an Exhibition mode, you just play a game with any team, against any other team, with your rules.
Season: You get to play up to 20 years in this game, with your team and eventually become Nippon Champions! And gradually get better, draft players, and get some players from America.
My Life: Play as either a Success Mode character, one you make at the beginning of the mode, or one of the NPB (Nippon Professional Baseball) players.
Success Mode: The main attraction of the Power Pros games. The fun RPG-ish mode, where you must play as a made character and make him (or her in this game) the best they can possibly be. In this game you can choose from 3 different success modes; One in which you're just playing for a local college, one in a military/very strict school (can't tell because it is in Japanese), or as a girl at a very fancy (and most likely expensive) school, in which you must assemble a team, and win Koshien (a summer baseball tournament). My favorite mode, and actually not hard, even without any knowledge of Japanese.
There are some others, but none worth going into.

Controls:
Easy as anything, X to swing, Circle to bunt, Triangle to steal, and Square to go back (I believe, I could be wrong)

Fun:
This game is a blast, and you should get it if you like baseball and/or the Power Pros series. I recommend it to anyone, even if they don't know Japanese. This is a great game, and I have ordered another one Jikkyo Powerful Pro Yakyuu NEXT for the Wii. Also looks good, I will most likely be reviewing that one too. Thanks for reading.

Pros:
+ Fun, engaging game
+ Addicting
+ Easy to understand though in Japanese
+ 3 different Success modes, all of which are fun

Cons:
- In Japanese