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Five years after their stinging loss in the '84 NLCS, the Cubs were back in the league championship series in 1989 against the San Francisco Giants.
This time, their nemesis was Will Clark, who hit .650 with two doubles, a triple, three home runs and eight RBI to kill Chicago's chances at reaching the World Series yet again.
Most notably, Clark hit a grand slam off of Cubs starter Greg Maddux in Game 1 of the series, in which he later said he read Maddux's lips when speaking to his catcher at a mound conference just before his bases-loaded at-bat.
Ever since, pitchers have covered their mouths with their glove to prevent the same from happening again.
Clark then hit a go-ahead single off of Cubs reliever Mitch Williams in the decisive game of the series, sending the Giants to the Fall Classic.