gotta tell you the truth; this has happened to me twice, it seems the better graphics you have, the more the game will function as his best. First of all, I was always saying that in BaL mode your partners were stupid, no matter if you were at Valencia C.F (which is a good team) you'd have a great chance to lose to the worst team of the Eredivisie League, there were a lot of bugs and stupid decisions your partners do, but look at this, I just upgraded my pc to Windows 7 (I was using XP), which has a new tech called WARP, that makes your CPU to act as a graphics accelerator, and it improved INCREDIBLY the graphics perfomance of my nVidia card, the 8400 GS (which is not really good at all), now the game runs better, the physics of the game are awesomely improved; I mean the ball makes more realistics moves, so do the players (and your Legend) and your companion's AI is improved too, they pass you the ball and awesomely they DO DRIBBLE OTHER PLAYERS, not always but at least they now do that, they make better passes, well whatever everything else is improved. If u're using pc try to improve your graphics, installing the latest drivers or upgrading your pc. And if you have the advantage to play PES 2009 in a PS3 or XBOX compare it to your PC's perfomance and you'll see probably they aren't the same if not well emulated.
Improving your graphics is real good, I wanted to share to you this since I think it can solve a lot of common problems. Bye.