The Dragons came within minutes of stunning Sheffield United - and now they know their reward if they can finish the job at Bramall Lane.
If they can see off the Championship side, they are at home to Tottenham Hotspur.
The fifth round will be playing midweek during the week commencing Monday February 27.
Paul Mullin’s 27th goal of the season four minutes from time had put the National League leaders within sight of the next round only for John Egan to make it 3-3 deep into additional time.
Phil Parkinson says he couldn’t have asked for any more from his side despite not being able to put the ten men to bed.
“It’s a mix of emotions. I am choked for the fans we haven’t got over the line and created history here,” he said.
“When that happens heads can drop quickly and people start looking around for excuses and there wasn’t any of that. I thought the lads were immense.
“These are a good side, as their league position suggests, and they have Premier League written all over them but we pinned them back for long periods and it’s a real blow we didn’t get over the line.”