The Heed looked to be all but out in the original tie at Brisbane Road, trailing 3-0 with just over 20 minutes to go.
But Watson’s men pulled off a remarkable comeback with Richard Peniket netting the equaliser in stoppage time.
The two sides will do it all again at the International Stadium and the Heed boss wants to make things tough for Orient.
“I’m looking forward to it!” Watson told the club’s YouTube channel. “You have to take the positives from the recent weather and it has given us the chance to let the lads recover from all the games and travelling.
“Hopefully we’ve coupled the training and rest together well. We had a good session last night at Newcastle which was great and many thanks to them.
“If we go into the game carrying the momentum from the last 25 minutes of the last match, it’ll be a tough place for them to come.
“We’ll be expecting a very tough game again but we’re desperate to do well in this competition and the onus will be on us to go for it.”
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