Here's a "missing" card for a player who appeared in 113 games in 1971, with almost 300 plate appearances, but didn't show up in the 1972 set, infielder Roberto Pena of the Milwaukee Brewers:
Granted, those 113 games were to be the final games of his Major League career, but this was pretty much a full-time guy so a card for him in this set is warranted.
Pena would play in the last of his six seasons at the big league level, coming up with the Chicago Cubs in 1965 at the ripe "old" age of 28.
He missed the 1967 season altogether, then made his way back in 1968 with the Philadelphia Phillies before moving on to the San Diego Padres in their inaugural year of 1969.
He then went on to split the 1970 season with the Brewers and Oakland A's, making it four organizations in three years.
But in all three of those years he was a legitimate full-time player, plating over 500 appearances each and every time.
In 1971 he saw that time cut almost in half, coming to bat 274 times with 65 hits, good for a .237 batting average.
And that, as they say, was that for Pena.
He played a few more years in the Mexican League, but would never make it back to the Major Leagues again.