County reached the semi-finals last season, famously beating eventual winners of the trophy Manchester United 1-0 at Pride Park before losing 4-3 on aggregate following defeat in the second leg at Old Trafford.
Clough insists his side must be fully focused in the first round against Rotherham on Tuesday night if they harbour any ambitions of landing another glamourous tie this time round.
"These are the tricky ties that you have to get through in order to get to the ties against the big teams, as we did last season," said Clough.
"And it will be a tricky game because Rotherham are a good team and the Don Valley Stadium, with the running track around the pitch, can be a strange place to go and play football if you are unaccustomed to it.
"Last season has gone now, it's a good memory but we must be at it against Rotherham to have any chance of repeating what we did in last season's competition."