Ethnikos’ two best runs in the Greek Cup in the 1970s were halted by PAOK. In 1972-72 Ethnikos lost to PAOK 3–2 in the Semifinals and in 1976–77 Ethnikos was defeated by PAOK in the Quarterfinals. Ethnikos made decent 7th-place finishes in 1979–80 and 1980–81, but the team would mostly struggle through the rest of the 1980s. In 1983–84 and 1985–86 Ethnikos reached the Quarterfinals of the Greek Cup but was then eliminated by Panathinaikos and Olympiacos, respectively. In 1986–87 Ethnikos made a very mediocre 10th-place finish, but late in the season earned one of their more memorable results – winning 6–3 away to Panathinaikos. The 1987–88 team was the last truly competitive Ethnikos team to date. That year Ethnikos tried to make a run at a UEFA Cup berth, but ultimately fell short and finished 7th. The 7th-place finish though was good enough to take some satisfaction from finishing ahead of Olympiacos, who finished 8th. In the 1988–89 season Ethnikos made a good run in the Cup, reaching the Semifinals before being eliminated by Panathinaikos, but in the league the team finished in the bottom 3 and was relegated to Beta Ethniki for the first time in their history. After being relegated from Alpha Ethniki for the first time in 1989, Ethnikos bounced between A' and B' Ethniki throughout the 1990s. Since a last place finish in 1998–99 though, Ethnikos has not managed to return to A' Ethniki. The Ethnikos teams of the 1990s included several young players who would leave the club and become star players elsewhere, such as Michalis Kapsis, Yannis Anastasiou and Andreas Niniadis. After the 1999–00 season Ethnikos fell from Beta Ethniki to Gamma Ethniki for the first time. The club’s ultimate low point came when it fell from Gamma Ethniki and spent the 2003–04 season in Delta Ethniki. In summer 2004 Ethnikos merged with A.O. Mani, the club maintained Ethnikos' logo and colors and continued to be based in Piraeus, but in name became Ethnikos Piraeus – A.O. Mani. Ethnikos fans were very upset with the name change, but that problem was eventually solved, as the club was officially renamed Ethnikos Piraeus in 2007.