The 1966 Cubs had just completed one of the worst months in club history, July of that year, in which they went 9-22. They had lost 12 of their last 15 and were 32-71, 39 games under .500 and 28 games out of first place, when they came home to begin a nine-game homestand at Wrigley Field.
Just 7,266 showed up at the old ballyard on a sunny, but windy afternoon, and the wind was a key factor in the result, as recapped by Edward Prell in the Tribune:
It was one of those unusual afternoons in Wrigley field yesterday, when a powerful wind blew fly balls off course and made fielding them a hazard. It was unusual, also, because the Cubs won for a change, tho the big blow from the lake did them no special favors. In fact, it kept Glenn Beckert's hardest drive of the season from ending the game in regulation time. Rather, the weirdest kind of base hit put into motion the run which beat the Atlanta Braves 6 to 5, in the twelfth inning, making Ted Abernathy the victim and Ferguson Jenkins the winner for just the second time. Felipe Alou confidently reached for Adolfo Phillips' half-speed grounder toward first base at the start of the decisive inning. But the ball, hit on the end of the bat, took a crazy spin toward Alou's right. He grabbed nothing but open air as the single dribbled into right field.
Beckert then sacrificed Phillips to second. Billy Williams was intentionally walked and Ron Santo struck out for the second out. After a wild pitch, Ernie Banks was also intentionally passed, and Byron Browne lofted a floater of a hit into right field to win the game.
The Cubs went 27-32 in August and September 1966, not great, but far better than the previous four months. It might have presaged the 1967 revival of the team to being a contender.
What's even more interesting about that boxscore is that five future Hall of Famers played for the Cubs that day. In addition to Banks, Santo, Williams and Jenkins, Robin Roberts made one of his nine Cub starts that afternoon. Roberts, long past his glory days for the Phillies, had been acquired by the Cubs a few weeks earlier after the Astros released him. This was one of just three games in which all five future Hall of Famers appeared for the Cubs.
In fact, counting the Braves who played that day, eight future Hall of Famers appeared in Wrigley Field that afternoon. Hank Aaron, Joe Torre and Eddie Mathews were in Atlanta's lineup. I can't imagine you could find many games where that many future Cooperstown inductees played.