Baseball Record
Apr 9 1st baseball game at Houston Astrodome, Astros beat NY Yankees 2-1 in exhibition as Mickey Mantle hits MLB's 1st indoor homerun; US President Lyndon Johnson and wife Lady Bird attend
US Masters Golf
Apr 11 29th US Masters Tournament, Augusta National GC: Jack Nicklaus wins the 2nd of his 6 Masters titles with a tournament record 271 (−17); beats Gary Player and Arnold Palmer by a record 9 strokes
- Apr 12 1st regular season MLB game at Houston Astrodome; visiting Philadelphia Phillies beat Astros 2-0
- Apr 15 NFL changes penalty flag from white to bright gold
- Apr 19 69th Boston Marathon won by Morio Shigematsu of Japan in race record 2:16:33
- Apr 25 19th NBA Championship: Boston Celtics beat LA Lakers, 4 games to 1
- Apr 28 Lindsey Nelson broadcasts baseball game at Houston Astrodome from a hanging gondola
Baseball Players
Basketball Stars
Boxers
Footballers
NFL Stars
Tennis Champions