It was 1980 that proved big for Cruz and the Astros. In 160 games for the team, he would hit .302/.360/.426 while garnering a selection to the 1980 Major League Baseball All-Star Game, the first ever for him. His efforts proved key to the Astros making the postseason for the first time in team history. To get to the postseason, the Astros had to win a tie-breaker game with the Los Angeles Dodgers. In the first inning, he helped to score the first run of the game after hitting a ball that got him to first base on a fielder's choice while scoring the runner on third base. The 1980 National League Championship Series proved a close series (all but Game One went to extra innings), and Cruz proved important in numerous games. In Game 2, he broke a 2-2 tie with an eighth inning single to score Joe Morgan. When the Phillies came back to even it, he stepped up in the tenth inning with runners on first and second on one out with a single that was the first of four runs in the inning as the Astros evened up the series. In the do-or-die Game 5, he scored the first run of the game on a two-out double in the first inning. An intentional walk in the seventh with two outs proved important as the Astros scored three runs on two subsequent hits and a wild pitch that scored Cruz. While the Phillies made up for it in the top of the eighth inning to lead 7-5, Cruz and the Astros fought back to tie in the bottom half, as Cruz helped score the tying run on a two-out single. However, the Astros could not hang on for the tenth inning, as Garry Maddox scored in the winning run on a two-out double to seal the fate of the Astros (who had lost the last two games needing just one more win for the pennant). On the whole, Cruz batted .400 with four RBIs, six hits, eight walks, and one strikeout.