Robbie Neilson said League 1 is the priority this season, not the Carabao Cup, after his side were dumped out 4-1 by Premier League Swansea on Tuesday night.
Despite taking a 17th minute lead through Ryan Seager, two Leroy Fer headers, one in either half, a Tammy Abraham tap-in and a great solo strike from Jordan Ayew saw the Welsh side comfortably through.
Neilson made seven changes to the side which started against Gillingham on Saturday, but said full focus should be on the game against Blackburn Rovers at Ewood Park this Saturday.
He said: "We knew it would be a tough night for us once we saw the teams, and we decided to rest a lot of our players. We've got a huge game with Blackburn on Saturday, so we saw it as an opportunity to play some of the younger lads.
"It was a great experience for them but the objective at the start of the week was to win at Blackburn.
"I know the fans will be disappointed, going into these games they want us to give it a go, but the main objective for this club is the Championship, so we have to focus on that.
"It's such a long season down here, so we can't play our same 11 week in, week out - they'll just break down and the guys who haven't played won't be ready. We have to use these games, and the Checkatrade Trophy as an opportunity to give guys game time so they're ready for the main campaign."
While handing debuts to Wieger Sietsma and Conor McGrandles, Neilson also gave starts to youngsters Giorgio Rasulo and Callum Brittain. And though they came out second best against a Swansea side which featured eight of the 11 which started against Manchester United on Saturday, the manager felt it was a good reference point for the side to see the difference in quality between League 1 and the Premier League.
"It's a huge learning curve for them," he said. "It's a reality check for some of them - you can go along in your little League 1 bubble where you think you're doing well, but it shows the improvements we have to make to get to that level.
"And I do believe there are players in our group who can get there, but it shows the huge steps they have to take.
"We competed well in the first half, but when you play these sorts of teams, they're always going to have a lot of the ball. We defended well, and managed to get ahead.
"The disappointing thing was not being able to hold onto the lead for long enough to put them under pressure. But in the second half, their quality shone through."
Seager was a late inclusion on the starting 11, stepping in when Kieran Agard complained of a potential groin problem in the warm-up
"Thankfully, there was a positive from deciding to rest Kieran late in the day," Neilson added. "It's great for Ryan to get him off the mark, and good play from Robbie Muirhead too help him get slotted through."