The Lions were successful during an opening-day outing in the Championship at the weekend, while Reading were unable to earn any points from their first match in the third tier.
Match preview
Any worries about a hangover from missing out on the playoffs last season were quickly banished on Saturday afternoon, with Millwall beginning their Championship campaign with maximum points on Teesside against Middlesbrough.
Gary Rowett's side were without the ball for large portions of the game against Michael Carrick's Boro, however the Lions' hard work paid off when substitute Romain Esse bagged a 79th-minute winner to send the away following at the Riverside Stadium into raptures.
Millwall now return to their London home in search of progression to the second round of the EFL Cup - a competition they have failed to go past the first stage in during two of the last three campaigns.
Two minutes of madness at Abbey Stadium in August 2022 saw Liam O'Neil score the decisive goal for lower-tier Cambridge United and Lions attacker George Honeyman sent off to knock Rowett's men out of last season's EFL Cup.
The Londoners' long-term record in the competition does not bode well for their success in the 2023-24 edition, with Millwall last making it past round three in the 1994-95 campaign - a season in which they reached the quarter-finals.
Reading are back in the third tier of English football for the first time in over two decades, and they were unable to get their campaign off to a winning start at the Select Car Leasing Stadium.
Peterborough were the visitors to Berkshire on Saturday and Darren Ferguson's men were in no mood to let May's playoff capitulation against Sheffield Wednesday stay in their minds for too long, with Ephron Mason-Clark's goal securing a 1-0 victory.
The Royals are now under the stewardship of Spaniard Ruben Selles, after the 40-year-old left his post at Southampton following their relegation to the Championship in the 2022-23 term.
Selles brings fresh ideas to Reading that will need time to bed in, and although an EFL Cup run would be appreciated by supporters, the club's main priority will be securing an immediate return to the second tier.
Reading have failed to make it past the first round of this competition in their last two attempts, falling short against Swansea City and Stevenage most recently.
Millwall form (all competitions):
Reading form (all competitions):
Team News
After such a gritty performance against Middlesbrough on the weekend, Millwall are likely to freshen up their XI for their midweek EFL Cup clash, meaning George Saville and Saturday's goalscorer Esse should be in from the start.
New signing Kevin Nisbet was preferred to Tom Bradshaw at the Riverside last time out, however the Welshman should be handed his first competitive start of the campaign on Tuesday night.
Aidomo Emakhu provided the assist for Esse's winner in the Lions' Championship opener, and the early stages of the EFL Cup should be a great stage for the 19-year-old to showcase his talents in senior football.
Reading are set to rest Andy Carroll during their trip to London, after the 34-year-old played the entirety of his side's defeat against Peterborough on the weekend.
With Kelvin Ehibhatiomhan the only other recgonised striking option for the Royals, boss Selles may opt to change systems to accommodate another midfielder, such as Lewis Wing or Mamadi Camara.
Tom McIntyre is set to be at the heart of the visitors' defence at The Den - the 24-year-old will play a big part in the club's quest for promotion from League One this season.
Millwall possible starting lineup:
Bialkowski; Harding, Cooper, Wallace; McNamara, Saville, Esse, Leonard, Voglsammer; Bradshaw, Emakhu
Reading possible starting lineup:
Boyce-Clarke; Mbengue, Rushesha, McIntyre, Guinness-Walker; Camara, Hutchinson, Savage, Knibbs, Wing; Ehibhationham
We say: Millwall 2-0 Reading
Millwall recorded a statement victory at Boro on Saturday and will return to The Den desperate to put on an exciting performance in front of their home faithful against League One opposition.