text: The next two seasons were unmemorable for the Army Men, finishing in fifth and second place respectively. In 1968, CSKA underwent another merger, joining with Septemvri Sofia and taking on the name of CSKA Septemvriysko Zname ("CSKA September Flag"). The club clinched the title in 1969 with the help of recent acquisition Petar Zhekov, who would go on to become the top Bulgarian goalscorer of all time, a record Zhekov held for 52 years until he was surpassed by Martin Kamburov in 2021.
  1970s
  The 1970s are widely considered the period when CSKA made its name on the European stage. The club began the decade modestly, claiming second place domestically and reaching the round of 16 in 1970–71 European Cup Winners' Cup, where they fell to English side Chelsea 0–2 on aggregate. However, from 1971 to 1973, CSKA won three consecutive titles and delivered one of the biggest surprises in European football when it eliminated reigning European champion Ajax – considered the finest team of all time – 2–1 on aggregate in the 1973–74 European Cup.
  They then faced German champions Bayern Munich in the quarter-finals. After losing 1–4 in the first leg in Munich, CSKA bowed out of the competition following a 2–1 win at home. Between 1975 and 1979, the club won two more domestic titles.
  1980s
  The 1980–81 season was again a memorable one for CSKA Sofia, winning the Bulgarian title once more and twice beating European champion Nottingham Forest, both times with 1–0 scorelines, before being stopped by the future European champions Liverpool with a 6–1 defeat on aggregate in the quarter-finals of the European Cup.