The Major League Baseball season of 1961 was prepared to commence with the annual ceremonies in Washington D.C. In a continuing tradition, President John F. Kennedy was in attendance at Griffith Stadium to throw out the ceremonial first pitch before the Washington Senators would take on the visiting Chicago White Sox. Players from both teams would position themselves on the field to battle for the cherished souvenir. The President executed a healthy toss that sailed over top of a number of players and was caught by Chicago White Sox player Jim Rivera. As Rivera recounts in a period audio recording, he guessed that the President would make a longer toss given his athletic abilities. Rivera then took the baseball to the President who signed the ball in addition to Vice President Lyndon Johnson who also added his autograph to the ball. Lightly toned Joseph Cronin American League baseball with President Kennedy having signed a side panel in blue ink, "To Jim-Good luck! John Kennedy" rating 7 out of 10. Vice President Johnson signed the adjacent side panel in blue ink rating 7/8 out of 10. Red/pink titling written on side panel in what appears to be Rivera's hand, "April 10, 1961 Opening Day Washington vs. Chicago White Sox". Period video shows Rivera catching the ceremonial first pitch and Lyndon Johnson signing a baseball shortly after which may well be the offered sphere. To the best of our knowledge the offered example represents the only documented baseball signed by both Kennedy and Johnson who for a number of reasons would become two of the most consequential Presidents in American history. Very important signature baseball with unimpeachable primary source documentation. Includes full LOA from PSA/DNA (Kennedy 7 NM, Johnson 6 EX-MT, Overall 6.5: EX-MT+), modern black and white image of Kennedy throwing out first pitch in 1961, and handwritten 1992 letter of provenance from Jim Rivera: Ball: EX, Signatures: Range EX/MT-NM/MT