Southampton had their hopes dashed at the last minute after a Steven Naismith goal deep into stoppage time gifted Norwich a replay fixture with the Premier League side.
The Saints went ahead after an impressive right-footed effort from in-form defender and captain Virgil van Dijk, but the home side soon broke even after Steven Whittaker converted from the penalty spot.
Southampton held their nerve and went onto to reclaim their lead through the most unlikely of goalscorers.
Japan international Maya Yoshida was on hand to beat Norwich 'keeper Michael McGovern but late drama would soon send the game to a replay.