Chiedozie Ogbene's strike proved to be the matchwinner as Rotherham survived a late Port Vale fightback to secure a 2-1 Carabao Cup win.
Oliver Rathbone opened the scoring for Rotherham early in the game and Ireland striker Ogbene added a second in first half injury time.
Substitute Mal Benning gave Darrell Clarke's League One underdogs hope with an 81st-minute strike, but Rotherham, without a win at Vale Park since 2013, held on for victory.
Tommy Conway's first career brace ensured Bristol City’s route into the second round with a 4-1 win against Coventry at the Pirelli Stadium.
The forward was starting for the Robins for the first time since May 2021 and netted a first-half brace inside half an hour after Kai Naismith opened the scoring.
Andreas Weimann wrapped things up deep into stoppage time after Jamie Allen had got one back for the hosts after 62 minutes.
The game was played at Burton Albion’s Pirelli Stadium after the pitch at the Coventry Building Society Arena was deemed unplayable following 65 Rugby 7s matches in just three days during the Commonwealth Games.
Josh Benson scored a last-gasp winner as Barnsley stunned Championship Middlesbrough to book a second-round trip to Leeds.
Benson netted with an injury-time rebound at the Riverside after Liam Roberts had saved his initial effort.
The League One side will now play their Yorkshire rivals Leeds at Elland Road after the draw for the next round, when a number of top-flight sides enter the competition, was made after the game.
Other notable ties will see League newboys Stockport host Leicester and Steven Gerrard's Aston Villa travel to Bolton. Wolves host Preston, Fleetwood take on Everton and Newcastle visit Tranmere.
Promoted Nottingham Forest will play at Grimsby while Norwich will host Bournemouth and Crystal Palace will head to Oxford. Fulham face an intriguing tie at Crawley, Southampton travel to Cambridge, Brighton visit Forest Green and Brentford are away at Colchester.
League One Sheffield Wednesday will join them in the second round after a comfortable 2-0 win over Championship Sunderland.
The Wearsiders denied the Owls a place in the League One play-off final last season but the South Yorkshire side exacted some revenge to set up a home tie with Rochdale.
Dennis Adeniran marked his return from injury with a stunning opener at Hillsborough before setting up the second for Sylla Sow.
Championship Blackburn will face former manager Mark Hughes’ Bradford after making easy work of League Two Hartlepool at Ewood Park. Rovers won 4-0 with goals from Scott Wharton, Bradley Dack, Tyrhys Dolan and Dilan Markanday.
Peterborough edged their all-League One clash with Plymouth 2-0 at Home Park. Ricky Jade-Jones grabbed their opener in the 28th minute before Joseph Taylor made victory safe in the closing moments. The win set up a trip to Stevenage.
The other ties in the second round are: Newport v Portsmouth, Watford v MK Dons, Walsall v Charlton, Gillingham v Exeter, Derby v West Brom or Sheffield United, Barrow v Lincoln and Shrewsbury v Burnley.
The line-up will be completed when West Brom play Sheffield United on Thursday.