|| 1–3 || Pascual Pérez (1–0) || Larry Christenson (1–4) || None || 20,695 || 23–15 |- style="background:#bfb" | 39 || May 23 || @ Pirates || 6–4 || Mike Proly (1–0) || Kent Tekulve (0–3) || Ron Reed (2) || 20,340 || 24–15 |- style="background:#fbb" | 40 || May 24 || @ Pirates || 1–7 || Jim Bibby (3–2) || Marty Bystrom (3–3) || Víctor Cruz (1) || 21,771 || 24–16 |- style="background:#fbb" | 41 || May 25 || @ Mets || 3–13 || Greg A. Harris (1–0) || Dick Ruthven (6–2) || Jeff Reardon (2) || 20,469 || 24–17 |- style="background:#bfb" | 42 || May 26 || @ Mets || 7–5 || Ron Reed (1–0) || Neil Allen (3–2) || Tug McGraw (4) || 13,973 || 25–17 |- style="background:#fbb" | 43 || May 27 || @ Mets || 1–3 || Pat Zachry (5–5) || Larry Christenson (1–5) || None || 10,930 || 25–18 |- style="background:#fbb" | 44 || May 29 || Cardinals || 4–11 || Bob Forsch (5–2) || Nino Espinosa (2–4) || Mark Littell (1) || 32,358 || 25–19 |- style="background:#bfb" | 45 || May 30 || Cardinals || 10–2 || Dick Ruthven (7–2) || Lary Sorensen (4–4) || None || 35,034 || 26–19 |- style="background:#bfb" | 46 || May 31 || Cardinals || 6–1 || Steve Carlton (8–0) || Silvio Martínez (1–4) || None || 54,103 || 27–19 |- |- style="background:#bfb" | 47 || June 1 || Mets || 5–4 || Sparky Lyle (4–1) || Neil Allen (3–3) || Tug McGraw (5) || 27,631 || 28–19 |- style="background:#bfb" | 48 || June 2 || Mets || 9–7 || Mike Proly (2–0) || Ed Lynch (1–3) || Ron Reed (3) || 25,375 || 29–19 |- style="background:#fbb" | 49 || June 3 || Mets || 2–6 || Greg A. Harris (2–1) || Dick Ruthven (7–3) || Neil Allen (5) || 27,588 || 29–20 |- style="background:#fbb" | 50 || June 5 || @ Braves || 1–4 || Rick Mahler (3–1) || Steve Carlton (8–1) || Rick Camp (8) || 17,059 || 29–21 |- style="background:#bfb" | 51 || June 6 || @ Braves || 3–0 || Larry Christenson (2–5) || Tommy Boggs (1–9) || Mike Proly (1) || 15,291 || 30–21 |- style="background:#bfb" | 52 || June 7 || @ Braves || 7–5 || Sparky Lyle (5–1) || Gaylord Perry (5–4) || Ron Reed (4) || 23,482 || 31–21 |-