Playoff Scenario's for Ohio State 

Guaranteed - Whoever wins is guaranteed a spot in the Playoffs
Spot 1: ACC Champion ( Clemson/ Miami) 
Spot 2: SEC Champion ( Georgia/ Auburn) 

Guaranteed if they win - These teams are guaranteed a spot if they win
Spot 3: Oklahoma  ( Beat TCU)
Spot 4: Wisconsin  ( Beat OSU) 

Possible Scenarios - Teams that have a shot 
Alabama - get's into the playoffs with an Auburn win over Georgia and a Wisconsin Loss

Ohio State - Get's into the playoffs with a win over Wisconsin and a Oklahoma Win and a Georgia win. 

Oklahoma win would improve our sos and 1 loss would be a high quality loss. 
A Georgia win devalues ALABAMA's high quality loss, into just a good loss. 

Clemson, Oklahoma, Georgia and OSU is the only scenario where OSU get's into the 4 team Playoff playoff. 

If Auburn win's (and OSU wins) Alabama is in over OSU. 

If we say all hell breaks loose and we have 
Miami beating Clemson, 
TCU beating Oklahoma, 
Auburn beating Georgia, 
Then Miami, Alabama, Auburn are Guaranteed a spot, ( switch Auburn and Georgia if Georgia wins) 
The 4th spot is then up for debate between USC and TCU probably with the edge going to TCU.    OSU would lose it's tiebreaker to Oklahoma, who will have just lost to TCU.