On June 12, 1970 the Pittsburgh Pirates' Dock Ellis pitched a no-hitter against the San Diego Padres. This feat would be fairly unremarkable if not for the fact he accomplished it with pupils the size of dinner plates. That's right. Dock Ellis started the game six hours into an LSD trip.
At 1 PM that day, one hour after Dock had taken acid in L.A., his girlfriend looked at a newspaper and noticed that Ellis was scheduled to pitch that day. She rushed him to the airport and he was in San Diego by 4:30 PM. The game started at 6:05 PM.
Dock started and pitched a complete game with no hits, but walked eight batters and hit one. About his performance that day, Dock said "I can only remember bits and pieces of the game. I was psyched. I had a feeling of euphoria. I was zeroed in on the [catcher's] glove, but I didn't hit the glove too much. I remember hitting a couple of batters and the bases were loaded two or three times. The ball was small sometimes, the ball was large sometimes, sometimes I saw the catcher, sometimes I didn't. Sometimes I tried to stare the hitter down and throw while I was looking at him. I chewed my gum until it turned to powder. They say I had about three to four fielding chances. I remember diving out of the way of a ball I thought was a line drive. I jumped, but the ball wasn't hit hard and never reached me."
Of course, this is only if you take Ellis' word for it. According to some teammates, Ellis showed no signs of being under the influence, and he seemed to have it together during a postgame interview. Even if he was on acid, considering he took it at noon, and the game started at 6:05, it's likely that he was well on his way to sobriety for the game's duration. It's also possible that he could have been still peaking or at least tripping rather hard during the game. All I know is, if LSD was as popular with athletes as steroids seem to be, there would be a completely different tone to the recent sports doping scandals.
Sources:
http://www.sirbacon.org/4membersonly/docellis.htm
http://www.erowid.org/chemicals/lsd/lsd_effects.shtml
http://www.snopes.com/sports/baseball/ellis.asp