This is another one for me. It too has its origins at spring training. Way back in 2002 me and my dad were at Yankees camp in Tampa and it just happened to be media day. We were on a railing outside the stadium that no longer exists when in succession Joe Torre, Derek Jeter, Jorge Posada and Mariano Rivera all walk past us. I was able to get all four of them on this baseball.
Nearly 15 years later at the National in Atlantic City I was finally able to add Pettitte to complete the Core Four.