Here is another original Willard Mullin drawing I ran into while pursuing the Heritage Auction catalog. (auction link) It dates to the 1956 season and prominently features mascots for the Dodgers, Giants, Braves and Reds.
The famed Brooklyn Dodger "Bum" is seen strutting his stuff while wearing a Sal Maglie button on his lapel. At the same time the NY Giants mascot is on the bottom right screaming "Sic Transit Gloria Fifty-One." In other words, our ol' foe is lamenting the prestige lost since their glorious 1951 season that saw Bobby Thomson hit a walk-off homer to win the pennant.