UFC Undisputed 2010

Honestly though it isnt the most legit way

i found it easiest to find a friend that has the game and go to ranked matches

set up a odd custom search

ie...

5 rounds
middle weight
dlc charecters off
connection quality to have priority
camp fighting off
ufc fighters only

and make sure you and your friend arent in the same fight camp or it wont match you to together

then have one person host and the other search for the same options

So a boosting way has been posted, I'll give a few tips for winning legit.

Always have the stamina bar on! This is so you can easily see when the best time to submit is.

Fight in heavyweight! Frank Mir and Minataruo Nogiuera are beast's at submission's!

Most people play with Brock Lesner and these two. Pick Nogieura. At the start let them throw a few punches to drain down there stamina, then clinch them (RS Toward opponent), When in the clinch, drop to your back, (LB + RS minor) When on your back only click left stick to attempt a Kimura, 90% of the time (If you have more stamina) You will win. Out of 43 sub wins, 32 have come in the first 2:30 seconds of round 1.