The first match of Stoycho Mladenov in the national team of Bulgaria is on 22 February 1978. The team plays a friendly away with Scotland in Glasgow. Bulgaria won 2:1 and Mladenov scored the winning goal.
„Being a national player was fantastic – remembers Mladenov. –I was very excited before the match. At that time I played for Beroe and the coach of Bulgaria was Tsvetan Ilchev. I have several moments with the national team which I will never forget. The big disappointment was the European qualification with Yugoslavia in Split .We had to win at any price. If we ended in a draw, Wales would go to Euro 84, and the Yugoslavs needed a success. Both teams attacked during the whole matach. We missed a lot of goal opportunities and Radi Zdravkov even had a shooting position just in front of the keeper in the last minute. He could pass the ball to Georgi Dimitriov, but decided to shoot. It cost us the participation in Euro 84. The Serbs scored in the next attack. We had a really hard time, but we had to move on.
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Bulgaria made it to Mexico 86. „We had one of the best coach in all history – Ivan Vutsov – continues Mladenov – He was a great psychologist, motivator and a tactician who was able to prepare us for every team .We were in one group with the European champions of France, Germany and Yugoslavia. It was a very hard group and everybody dreamt of moving forward. We lost the first match with France in Paris. The referee had to score a penalty againsyt me, but instead awarded such to the home team and Platini scored it. We managed to win the next game in Sofia with 2:0. It has been one of the strongest matches of Bulgaria. I played on injections due to a shoulder problem, which continued all my life. I managed to score one of the most important goals in my career against the team of Germany three minutes before the end of the game from a free kick. We made it to the World Cup .
Ivan Vutsov made a tactical mistake before the World Cup. The team goes to a camp too early in order to get used to the climate. In our last match in Bulgaria we beat the team of Denmark 3:0. We lost a lot of weight due to the hard climate conditions. I was 4 kg below my normal weight and the Argentinian players were in perfect form. The climate affected our stamina, form and behavior on the pitch. It was very hard playing matches every three days..“
The first match of Bulgaria was against the world champions of Italy and ended 1:1 on Azteca Stadium.
„There is no such feeling as knowing that the whole world is watching you. I suffered an injury at the end of the match with Italy which made it hard for me in the next two games, but I played them .“
At the World Cup in Mexico Mladenov plays for the first time against Diego Maradona. . The first one was a friendly in Buenovs Aires. When he made it on the pitch the whole team shouted his name. He was the last one to appear and the fans sang his name the whole match. We lost 1:2 and I scored the goal for Bulgaria..Maradona scored a similar goal to the one against England years later. He passed through six players and nobody could take the ball. I have seen such a play only on the street. For Diego it was like a child’s play. At the World Cup I met him for the second time. We did our best against them, but lost 0:2.
After the World Cup the coaches did not include Mladenov in the national team until 10 May 1989 when he played for the last time in the national team..Liuboslav Penev suffered form an injury and nobody could play in attack. We won over Denmark 5:0 . I was 32 years old and all the other players were in their early 20s. Being a national team player was a great honour. I played in 65 matches, on a World Cup as well. I remember only the good times.“