Brighton boss Graham Potter says injuries and sickness forced him to field a youthful side for the Carabao Cup third round loss to Aston Villa.
Potter named a starting XI with an average age of just over 21 and handed 10 senior debuts to academy players during the course of the 3-1 defeat at the Amex Stadium.
After falling behind to first-half goals from Jota and Conor Hourihane, a header from 17-year-old defender Haydon Roberts briefly gave the hosts hope of forcing a penalty shoot-out, until Villa substitute Jack Grealish put the result beyond doubt.
Asked if he could have included more experience to his line-up, Potter replied: "Not really, not with the situation we've got – a couple of injuries, a couple of lads sick as well.
"So we're just going through that little phase at the moment.
"In the last round we were able to do a bit more experience and it would have been preferable to have a couple more around but it wasn't to be at this stage.
"A couple were close but it just wasn't worth the risk really."
Injury-stricken Albion have not won a Premier League game since the opening day and face daunting upcoming fixtures against Chelsea and Tottenham.
Experienced centre-back Duffy added to their concerns by limping off during the second period, leaving Potter with an anxious wait to discover the extent of the problem.
"It sounds like something in his calf. It's obviously a concern, we'll see how it settles down next 24, 48 hours," said Potter.
Despite being knocked out, Potter was pleased with what he saw from his team, who hit the crossbar through the lively Connolly before Roberts eventually halved the deficit.
"It was a spirited performance from our boys, they gave everything, up against a quality team that deserved to go through," he added.
"We had to stay in the game in the second half, which we did, and the goal is nice for our players to experience that moment of joy.
"And then they bring on Jack Grealish to get over the line. In the end it's a good experience for our players, it gives us an idea of what they need to do, but clearly you can see the quality difference as well."
The visitors' victory earned them a fourth-round clash at home to West Midlands rivals Wolves.
Villa boss Dean Smith praised the professionalism of his players after they avoided a potential upset against inexperienced opposition.
"As a Villa supporter, I've seen teams that have come unstuck in situations like that, whether it's a youthful team or a lower-league team," said Smith.
"The words I said to them were attitude, application and teamwork and I thought we got that in abundance tonight and they have done it right.
"This football club has got a very proud history in all cup competitions – we've won this five times, we've won the FA Cup seven times.
"You've seen the numbers that have travelled down from Birmingham and they deserve our utmost respect – and we've given it that tonight."