Monaco coach Claudio Ranieri congratulated Guingamp for convincingly mimicking his high-flying side to shock their way through to the Coupe de France final.
The principality club - second in Ligue 1 behind only Paris Saint-Germain - were favourites to book a final showdown with Rennes but it was instead struggling Guingamp who pulled off a 3-1 extra-time victory to reach the Stade de France.
Despite watching another chance to claim silverware slip from his grasp, Ranieri feels no real sense of shame about the result and admits Guingamp were great value for their win.
"It's a huge disappointment," he told L'Equipe. "We have 69 points and are fighting for a Champions League place while Guingamp are battling to stay in Ligue 1.
"But I think Guingamp were Monaco tonight.
"They played really well and were really organised so congratulations to them.
"Am I embarrassed? No... the team is always simply an expression of the coach's character.
"I may have lost this battle but I fought hard, I gave everything.
"But one team managed to get there and congratulations to Guingamp, who deserved to win 4-0."
Mustapha Yatabare and Dimitar Berbatov exchanged first-half goals but neither side could find the net again inside 90 minutes and the game went to extra time.
Substitute Fatih Atik then grabbed the vital goal with eight minutes remaining and Yatabare sealed the win five minutes later.
Guingamp may not be a household name outside of France but the Brittany club have form in the Coupe de France, winning the competition - at the expense of Rennes - in 2009 and losing the final to Nice in 1997.
But coach Jocelyn Gourvennec's immediate priority is guiding last season's Ligue 2 runners-up to safety in top flight as, with only five games remaining, Guingamp are only five points clear of 18th-placed Sochaux.
He said: "There is a huge feeling of happiness, of course, and it's a great step forward.
"We were the small side tonight, and people already had Monaco-Rennes down as the final.
"But we took our chances and managed to stay one step ahead.
"I've told the players that they've achieved something special and that we have a wonderful match to look forward to on May 3 at the Stade de France.
"But before then, we have two crucial games (against Bordeaux and Valenciennes) in our battle to stay in the league."