US Men's Tennis Open
Sep 10 US National Championship Men's Tennis, Forest Hills, NY: John Newcombe of Australia defeats American Clark Graebner 6–4, 6–4, 8–6 for first of 2 US singles titles
US Open Women's Tennis
Sep 10 US National Championship Women's Tennis, Forest Hills, NY: Billie Jean King defeats England's Ann Haydon-Jones 11–9, 6–4 for first of 4 US singles crowns
- Sep 16 Anni Pede runs female world record marathon (3:07:26)
- Sep 17 New Orleans Saints 1st NFL game, they lose to LA Rams 27-13
- Sep 18 Intrepid (US) beats Dame Pattie (Australia) in 21st America's Cup yacht race at Newport, Rhode Island
- Sep 22 Phillies release pitcher Dallas Green, their future manager
- Sep 24 NFL St. Loius Cardinals' Jim Bakken kicks 7 field goals at Pittsburgh Steelers, setting NFL record at the time
Baseball Record
Sep 27 Philadelphia Phillies pitcher Jim Bunning ties NL record of 5, 1-0 losses in a year
Griffith vs. Benvenuti
Sep 29 American boxer Emile Griffith regains his world middleweight crown on points in a brawling re-match with Italian Nino Benvenuti at Shea Stadium, NY; second of famous trilogy of fights