OXFORD United's giantkilling result was a fair reflection on the game, according to Swansea City manager Alan Curtis.
A double from Kemar Roofe, along with a penalty from Liam Sercombe, saw the U's - 55 places below the Swans in the league pyramid - through to the fourth round with a 3-2 victory.
It was the first game in charge since Curtis, who took over as caretaker boss last month, was named as manager for the rest of the season.
And the former Wales international had no complaints over the outcome.
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He said: "Today was hugely disappointing for ourselves.
“The only time we looked like a team was when we went 3-1 down - only then did we start to play but it was too late then.
“All credit must go to Oxford, I thought they were excellent today.
"They were much more energetic, they passed the ball and were the better side overall."
While United were unchanged, Swansea swapped their entire side, with the exception of midfielder Jack Cork.
Curtis defended the selection, which still contained four senior internationals and another quartet who had represented their country at under 21 level.
He said: “We made a lot of changes with Wednesday’s game against Sunderland in mind but we made similar changes over the Christmas period against Palace and produced a battling performance there (a 0-0 draw) but we did not repeat that today.
“We fielded players with lots of Premier League and international experience.
"The team we fielded was good enough but did not produce a result, which is hugely disappointing.”
- Reaction at full-time, via the FATV Youtube channel