I played an entire season and playoffs of Madden in one day. Quarters set to 5 minutes though, so with stoppages games are about half an hour. I guess that is around 10 hours but I didn't play 10 hours straight. Played for a few hours in the afternoon and then went and did other things for awhile and played the rest at night until around 3am.

This was before my daughter was born. My wife and son were out of town visiting family. I stayed home to finish up some work stuff in the morning but I didn't have anything to do in the afternoon so I just started playing and then went back to it later and it got to a point where I was so far in the season it just made sense to finish it.