If you have a really good cable system, you've got yourself a really great research library for making connections in the TV Universe. I have access to at least ten different cable networks which showcase classic shows from the past in which I can find those little bits o' trivia which I might not have noticed when those shows first aired; back before I began hunting such items down in earnest.
Here's a case in point: the GoodLife Network has a great schedule full of such shows as 'Maverick', 'Cheyenne', 'Kung Fu', '77 Sunset Strip', 'Hawaiian Eye', and 'The Man From UNCLE'.
They also show 'I Spy'. And this past week they broadcast the pilot episode, which didn't make it on the air until the 14th week of the series:
"Affair in T'Sien Cha"
Kelly and Scotty's investigation of the disappearance of an old Chinese train between Hong Kong and the Communist mainland leads to an ancient walled city, a beautiful American schoolteacher, and a secret cargo someone is willing to kill for.
b: 29 Dec 65
w: Morton Fine & David Friedkin d: Sheldon Leonard
During the episode, a local schoolteacher tells Kelly that she saw him play tennis three years before in Forest Hills, Queens. He was beaten (in straight sets, I believe) by Pancho Segura.
That means, even though it was off-camera, Pancho Segura makes himself an official Toobworld character in 1962.
I love these little mentions of real people in fictional scenarios during a TV show. Most of the time you can then link that person's "character" to other appearances in which they portrayed themselves. George Burns, Milton Berle, Sammy Davis Jr....... they're among the celebs who were most famous for this.
And Pancho Segura was no exception. True, he didn't appear in this episode, but it was stated as fact by the schoolteacher and so it really did happen in the TV Universe. (And the fact that Kelly backed up the statement - by requesting that she not remind him of that particular loss - cements the deal.)
Segura did, however, appear in a later episode of 'I Dream Of Jeannie':
"Always on Sunday"
(episode # 2.2)
19 September 1966
032 - Thinking Tony works too much and too hard, Jeannie makes one Monday a Sunday. For relaxation, she sends him to a safari in Africa, and then to play tennis. Ignoring Tony, she makes every day Sunday.
Tony, thinking it's Monday, sounds insane to Roger and Dr. Bellows when they drop by.
According to the IMDb.com, the only other TV appearance made by Segura happened during a show hosted by Jimmy Connors on ESPN. And although it would ultimately count, it lacks the oomph of a fictional setting.
But we'll keep looking. The TV Crossover Hall of Fame could always fit somebody who chases his balls in Toobworld.