1938 Chicago Cubs
Time distorts all perceptions. There are those of us who only think of the Cubs as that team that won the World Series in 2016 and how they had a massive title drought beforehand. Then there are those of us who lived that drought, watching those lovable losers fail year after year after year until their streak of futility hit 100 and even then it kept going. Some blamed luck, other blamed bad ownership, the rest pointed fingers at a goat (no, literally). Perhaps it was a combination of things (but not the goat) but the fact remained that the Cubs never stopped trying to get back to the top of the mountain despite the amount of times they'd get smacked back down.
In 1938, the Cubs were back again trying to climb that mountain. The previous season saw them win 93 games but finish a close 2nd for the pennant behind the Giants, and '38 didn't start too promising. By late July, the Cubs were in 3rd place and trailing the Pirates by 6 games. The decision was made to drop Charlie Grimm as Manager and install Catcher Gabby Hartnett as Player-Manager. Things picked up, and the Cubs staged a comeback in the home stretch of the season.
In the final week of games, the Cubs met the Pirates at home and just a half game back of 1st place. The game was tied 5-5 in the 9th, and darkness was threatening to cancel the game. By rule, if the game was called due to darkness in a tie game, it would be replayed from the start the next day. With 2 outs, Gabby Hartnett stepped in and hit a walk-off homer to win the game for the Cubs, putting them into 1st place where they'd never relinquish. The "Homer in the Gloamin" would ultimately put the Cubs back in the World Series.
Despite the momentum and the excitement of how they clinched the NL, the 89-63 Cubs still had to contend with a dynasty if they wanted to win the World Series. Waiting for the Cubs were the 2-time defending World Series champion New York Yankees. There would be no dramatic victories by Chicago, as the Yankees easily swept the Cubs 4-0 to take their own 3rd straight title.