Nigel Clough praised the measured and composed performance of his team following Tuesday's dramatic Capital One Cup success against the MK Dons.
United trailed as Benik Afobe scored from the penalty spot after Craig Alcock had impeded Dele Alli, but Clough was delighted to see his players remain patient and stick to the gameplan, rather than panicking and chasing the game.
The Gaffer, who was forced into a handful of changes to his starting XI, said: "We had to make changes because of injuries, but that shows we have options in the squad and whoever plays will never let anyone down in terms of effort and desire.
"We don't panic when we fall behind, we don't go throwing four up top and launching balls from back to front, we keep our shape, stick to how we want to play and the belief doesn't ever go.
"We keep playing, keep believing and thankfully it is working for us. We are now in the quarter-finals of the League Cup, it is an incredible achievement.
"We were keen to avoid extra-time and thankfully we did, with a big game on Saturday the last thing we needed, MK Dons probably thought the same, was another 30 minutes with the possibility of penalties."