On August 31, 1990, Ken Griffey Sr. and Ken Griffey Jr. became the first father-son duo to play in the same Major League lineup. Playing for the Seattle Mariners, the Griffeys started in left field and center field and second and third in the lineup, respectively. Griffey Sr. was 40 years old and towards the end of his career, and retired in 1991 after playing just 30 games. Despite Senior not playing as much as Junior and being at the tail end of his baseball career, the two formed a formidable duo at certain points—in their debut together on August 31, they hit back-to-back singles, and later in the season, they hit back-to-back home runs. Only one more father-son duo joined the Griffeys to play together, Tim Raines Sr. and Tim Raines Jr. The Griffeys remain to this day one of the most talented father-son duos to not only play on the same team but to play in the Major Leagues.