(PLEASE NOTE: IF YOU'VE ALREADY STARTED A MY PLAYER CHARACTER IN NBA2K10, THIS WILL NOT WORK. YOU WILL NEED TO DELETE THE SAVE FILE AND START HIM OVER FROM THE CHARACTER THAT'S IMPORTED FROM THE DRAFT COMBINE)
1. Download the Draft Combine from the Xbox Live Arcade, play all of your games, and Upload him to the 2K Server.
2. If you've previously played NBA2K10, go into your System Memory and delete the My Player Career file that's on your hard drive for NBA2K10. To find your system Memory, from the Dashboard go to My XBOX, scroll to the right and go to System Settings and select Memory. Find the NBA2K10 files and delete the Career File.
3. Load up NBA2K10 and it will connect to the server and re-download the NBA Today features and everything else that it pulls from the server. After it's downloading all that, hit the Right Thumbstick and go to Options, then My NBA, then Gameplay.
4. Change the minutes to how every much you want (I go with 9), then hit B to back out a screen, then press B one more time (so you're back in the Options Menu and go to Load/Save. Go to Save Settings on the left, and manually save the settings you just changed.
5. To verify the minutes changed, go back to the Main Menu and click on Quick Game. When it comes up to select a team, Press Y to bring up the game options. The Quarter Length should say 9 minutes.
6. Go back to the Main Menu and go to My Player. Click Continue and it will ask you if you'd like to Load My Player or Import My Player. You want to Import My Player and the game will connect to the 2K server and download the My Player you uploaded from the Draft Combine.
7. One your player is Drafted, and you go to play your Summer League games, the quarters should be set to 9 minutes (or whatever you chose to set them to)
And there you go! Now you're all set up and ready to play!