Ken Griffey Sr. once revealed his greatest achievement in famed MLB career

On September 14, 1990, Ken Griffey Jr. and Ken Griffey Sr. etched their names into baseball folklore. The father-son back-to-back home run achievement is one that will most likely never be replicated again in our lifetimes.

Ken Griffey Jr. is regarded as one of the greatest players in modern-day baseball. Ken Griffey Sr., however, could make the case that he taught Jr. everything he knows.

"31 years ago today, Ken Griffey Sr. and Ken Griffey Jr. gave us this iconic moment and went back-to-back.They became the first father-son duo to homer in the same game" - SportsCenter

Few remember how good of a player Griffey Sr. was. The outfielder had an illustrious career that included winning two World Series championships.

Ken Griffey Sr. was part of the historic Cincinnati Reds “Big Red Machine” team that won consecutive World Series in the 1970s. He was fortunate to play alongside some of the MLB’s greatest players including Pete Rose, Tony Perez, Johnny Bench, and Joe Morgan.

After leaving the Reds in August 1990, the Seattle Mariners signed Griffey Sr. and reunited him with his son.

Ken Griffey Sr. played alongside his son Ken Griffey Jr. during the 1990 MLB season

Former Mariner Ken Griffey Jr. waves to the crowd during a jersey retirement ceremony at Safeco Field

What followed turned out to be one of the most sensational moments in MLB history. Ken Griffey Sr. took the lead batting second in the lineup. His home run against the Angels set the stage for his son.

Griffey Jr., however, was not to be outdone. The 20-year-old prospect was already rated as one of the league's star prospects. With over 34,000 fans in attendance, Jr. had a point to prove. He did not disappoint.

"Ken Griffey Sr. grounded Ken Griffey Jr. and took his car keys after he cut him off to catch a fly ball" - Talkin' Baseball

Griffey Jr. drove a low pitch to left field and cleared the fence. It was a memorable moment for baseball fans everywhere.

"Being a father, I guess it's a dream come true," said Ken Griffey Sr.

The feat will almost certainly never be repeated. A father and son playing on the same team is unusual. The chances of both of them hitting back-to-back are extremely slim. For decades to come, the baseball world will remember what was truly a once-in-a-lifetime moment.