A Millwall side featuring a number of youngsters were narrowly beaten by Swansea City in an entertaining Johnstone's Paint Trophy first round encounter at the Liberty Stadium.
Jamie O'Hara and Jay Simpson made their full debuts whilst Preston Edwards got his first competitive run-out as a first half sub and youth team midfielder Tom Kilbey was introduced just before half-time.
Millwall started the brighter with Ben May, Scott Barron and O'Hara all going close early on before Paul Anderson gave the home side the lead on the quarter hour, finding himself unmarked at the far post to convert Darryl Duffy's right wing cross.
The lead only last four minutes, however, as May equalised from ten yards following good work from Simpson.
Chances came and went at either end in a very open first half which saw Edwards introduced for Chris Day after just 20 minutes and Kilbey for Dunne three minutes before the break.
Millwall got their noses in front on 53 minutes when O'Hara and Kilbey combined well to set up Simpson who rifled home from an impossible angle.
The turning point came with Swansea's double substitution on the hour mark.
Jason Scotland made an impact within five minutes of his arrival, cracking the ball in from 12 yards to make it 2-2, before the unfortunate Zak Whibread got the final touch to a cross from Thomas Butler on 77 minutes, sending the ball into his own net for the eventual winner.
The Lions came close to another leveller with a Chris Hackett free-kick in the dying seconds, only for keeper De Vries to save, throw the ball long to Anderson who collided with O'Hara leading to the Millwall midfielder harshly getting his marching orders.
There was much to cheer for Millwall, but as on Saturday, their luck was out.
Swansea City: De Vries. Austin, O'Leary, Duffy, Lawrence, Monk, Rangel (Amankwaah, 11mins), Bauza (Scotland, 59mins), Anderson, Butler, Craney (Pratley, 59mins). Subs not used: Knight, Robinson.
Millwall: Day (Edwards, 20mins), Senda, Frampton, Robinson, Whitbread, Dunne (Kilbey, 42mins), Hackett, Barron, May (Alexander, 46mins), O'Hara, Simpson. Subs not used: Bakayogo, Fuseini.
Ref: A.Penn
Bookings: Monk (Swansea) 90 mins, Hackett (Millwall) 61 mins, Whitbread (Millwall) 90 mins.
Sending-off: O'Hara (Millwall) 90 mins
Attendance: 5,721 (Away fans: 43)