Relegation from the Yugoslav First League
In the 1970/71 season, the club's fourth in the Yugoslav First League, the Purples were just as successful as in the previous three seasons. After a series of solid results and having drawn the last match of the season at home against Velež with 1-1, the team collected enough points to finish in 13th place. The season that followed proved to be the turning point as they were relegated from the top division. After 5 years of playing against the best clubs in Yugoslavia, NK Maribor had to return to second league. All their hopes were smashed on the 30th matchday (out of 34) when they only managed a goalless draw with Vardar at Ljudski vrt. They finished the season in the last place with 20 points. The last match in the first league was a 3-6 home defeat against Olimpija on 11 June 1972. NK Maribor played with the following players: Vabič, Petrič, Bolfek, Bradvić, Simeunović, Rašević, Krajnc, Vučeković (Dobrijević), Kukanja, Prosen (Klančnik), Horjak. The goalscorers for Maribor were Vučeković, Krajnc and Klančnik who remains NK Maribor's last player to get on the scoresheet in the Yugoslav First League.


20,000 fans at the game against Proleter
Once again, the team was playing in the second league. The players were showing character and playing remarkably. The 7-1 win against Rijeka on the last matchday in front of 7000 fans at Ljudski vrt only confirmed the second place finish, which guaranteed a playoff for the promotion to the first league. After a dramatic win against Budučnost (the match was decided by a penalty shootout), Maribor faced Proleter Zrenjanin. The first leg was played at Ljudski vrt and will always be remembered as one of the matches that kept football fans in Maribor up all night. 8 July 1973 was a special day. This was the match that would decide who would gain promotion to the top division and it drew so much attention that the stands were full two hours before the kick-off. There were no more tickets left to sell on the day of the match because they had all been bought in advance. According to the estimates, the match at Ljudski vrt was attended by 20,000 fans. Some fans entered the stadium without tickets as the otherwise solid concrete fence could not withstand the pressure from the mass of the crowd. One of the pillars collapsed and by the time the police arrived at the spot, many fans had already sneaked into the stadium. The Purples rewarded the fans with an excellent display and comfortably won the game with 3-1 (the scorers for Maribor were Binkovski, Horjak and Vučeković), which put the team in a good position before the return leg. Zrenjanin was feeling the pressure. In the anticipation of the decisive match, Proleter’s technical director Miloš Milutinović assaulted one of the journalists who reported that a number of their players intentionally played the first match poorly because they had already been sold to other clubs. The reporter ended up in hospital, but sadly for us, Proleter managed to get what they wanted. Maribor lost with 3-0 and the dreams of once again competing with the best teams in the country were over. Proleter seized the opportunity and with the help of its fans managed to turn the game around. Sadly, the game left a bitter aftertaste. In the 23rd minute and with the home team 1-0 in front, Maribor player Ražić scored a goal that should have stood as the camera replays later confirmed, but referee Spasoje Medić waved the players to play on as he decided that the home defender had managed to clear the ball before it crossed the line.


Never back in the top division
After that unlucky defeat, things did not go particularly well for NK Maribor. In the following season they could not keep up with the best teams in the second league. They finished in 13th place, barely avoiding relegation. In the 1974/75 season and after 14 years of playing in the first or second tier, the team was relegated to the Republic League, although only for a year. They clinched the republic title in their first attempt and gained promotion back to the Second League with a 15-point lead at the top. They remained in the Second League till the end of the decade and almost managed to qualify for the First League in the 1978/79 season, which they ended in 2nd place behind Čelik.