James Fowler says Sunderland's win over Morecambe provided 'all the things we were looking for'.
A late winner from Josh Maja secured top spot in the group and a home draw for the next round.
It means the Black Cats now have eight consecutive wins in all competitions.
A number of senior players were able to get game time while five youngsters made their debuts.
Two more, Jack Diamond and Lee Connelly, made their second appearances for the club.
Fowler said they took their chance and paid tribute to the work of the academy staff.
"It was all the things we were looking for.
"It was a good balance tonight. The first 15/20 minutes was hectic but after that we dominated the game, even if we didn’t created as much as we would have liked. That final bit was lacking in the final third but Josh Maja did what he does and it was nice to get the win.
"All the youngsters did really well tonight, it’s credit to the work being done by Elliott Dickman and the others in the academy.
"I thought Glenn Loovens looked after the defence really well, and for Jack Bainbridge to come in, he showed he’s capable of playing at this level and that’s a good one for us because we haven’t seen too much of him. The other ones higher up, Jake Hackett showed he has real quality. They all did themselves proud.
"They’ve come in and taken their chance and shown they’ve got the ability. This competition at the minute is a less pressurised environment than a league game but it was still one that we wanted to win and we’ve still prepared like we do for other games, so they’ve been able to see that and get an understanding of it."
Fowler said the win showed the big picture is bright for Sunderland, even if U23 results have been poor this season.
"It was pleasing to get the win but the staff and the manager are always looking to progress young players and I think it showed that there is good players in the academy.
"I know there’s sometimes a negativity because of the U23 results but the manager has said previously, it’s about progressing players and there’s players out on loan as well, so the bigger picture looks bright."