That raised the dispiriting possibility of a visitor’s winning the World Series on the Cubs’ grounds. It happened in 1945, when Hal Newhouser pitched the Detroit Tigers to a Game 7 victory at Wrigley and sent the Cubs into a World Series hibernation that lasted seven decades.

But losing in quite that fashion — by dropping Games 3, 4 and 5 at home to finish the series — is a rare kind of indignity, last suffered by the Philadelphia Phillies in 1983. The Cubs essentially felt it last season, by losing the last two games of an N.L.C.S. sweep to the Mets at Wrigley.

“The Mets beat us, and we had to hear all about that for the full season, even when you win 103 games,” catcher David Ross said. “It’s always something. I’ve learned that in the game. There’s always something to overcome, there’s always ‘How you gonna do this, how you gonna do that?’ This group has answered the bell.”

That was a fitting figure of speech. Before Game 5, the Cubs showed various “Rocky” movies on the clubhouse TVs. Rizzo did his best Sylvester Stallone for his teammates, and he had the Wrigley Field sound system play the theme song before his first at-bat. Yes, “Rocky” might be a cliché by now, and Chicago is a long way from South Philly — but the Cubs could relate.

“Just let everyone know we plan on going the distance,” Rizzo said that night. “Obviously, there’s a lot more that goes into that, but we bought in and we believe in it.”

The Cubs fell behind in Game 5. It was only 1-0, in the second inning, but still: The Indians had not gone from leading to trailing in any game this postseason. Yet in the fourth inning of Game 5, they did, with the Cubs’ offense showing all the ways it could score: with power (a Kris Bryant homer), speed (a Javier Baez bunt single) and situational hitting (a Ross sacrifice fly).