Alex Karras, who plays football player Jake Metcalf in this episode, actually played pro football in the National Football League (NFL) for the Detroit Lions team from 1958 to 1971 as a defensive tackle during his entire career.
The title comes from the punchline, "That was no lady, that was my wife."
This episode (which aired in 1973) shows Jake Metcalf and his football team in the locker room at Yankee Stadium, known for baseball and the New York Yankees. This would not be unusual, as the National Football League team the New York Giants played in Yankee Stadium from 1956 through 1973. Jake's team in the episode went unnamed however.
This episode ignores the fact that Felix has been in a serious relationship with his neighbor, Miriam, for several years. He even says that he hasn't had a serious girlfriend since his divorce from Gloria.