Nottingham Forest were taken to a replay by non-league Salisbury City, while Bristol City survived a scare before seeing off Gillingham.
Forest's trip to the Conference South high-flyers looked tricky on paper and so it proved as they were stretched to the limit in Wiltshire.
Things looked good for the League One leaders when Nathan Tyson fired them ahead on 27 minutes, but they failed to ram home their advantage and were pegged back on the hour.
Matt Tubbs showed great quality to swivel free inside the box and shoot past Rune Pedersen.
Both sides had the chance to win the game, but there were no further goals as both clubs entered the hat for round three.
Phil Jevons was the hero for Bristol City in their 4-3 victory over Gillingham.
Jevons helped himself to a first-half hat-trick as The Robins moved into round three.
The Gills contributed to their own downfall as some slapstick defending gave Jevons the opportunity to score on 21 and 44 minutes.
Jevons' third came in the fifth minute of first-half injury-time, after Gills keeper Kelvin Jack had been given lengthy treatment following a tangle in the area.
Gary Mulligan threatened to spark a revival when netting at the start of the second-half, but Enoch Showunmi nipped the comeback in the bud with a goal just past the hour.
Michael Flynn headed home on 66 minutes to get The Gills back within two goals and he slotted home a penalty with a minute remaining, but they could not find a leveller to force a replay.