Here are a couple things to try...
1) Usually come out in shotgun simple way to buy a little extra time.
2) If the pressure is coming from the A gap (Up the middle) try some runs off tackle with the opposite Guard or Tackle pulling across. Sometimes you cna break this for giant gains if the blocking sets up right.
3) Use Line Adjusting (I forget the name). Click LT I think and then switch your line blocking to something different. For example if the pressure is coming from the A gap pinch the line.
4) You can always leave RBs into block and/or motion WRs/TEs to block. Easy way to counter nanos.
5) And just remember nanos always have weak spots. It might be the flats, it might be the middle and it could be the run. Just stay calm under the pressure and nanos are easy to beat.