|| 3,001 || 12–12 |- style="background:#fbb" | 25 || May 8 || Astros || 7–9 || Jack Billingham (2–2) || Gary Wagner (0–2) || Fred Gladding (4) || 2,113 || 12–13 |- style="background:#bbb" | – || May 9 || Braves || colspan=6 | Postponed (rain); Makeup: July 29 as a traditional double-header |- style="background:#fbb" | 26 || May 10 || Braves || 3–6 || Pat Jarvis (2–2) || Grant Jackson (3–3) || Cecil Upshaw (7) || 7,313 || 12–14 |- style="background:#fbb" | 27 || May 11 || Braves || 3–4 || Phil Niekro (6–1) || Turk Farrell (1–1) || None || 4,105 || 12–15 |- style="background:#fbb" | 28 || May 13 || Reds || 4–6 || Clay Carroll (2–3) || Turk Farrell (1–2) || George Culver (1) || 4,474 || 12–16 |- style="background:#fbb" | 29 || May 14 || Reds || 2–4 || Jim Merritt (3–2) || Grant Jackson (3–4) || George Culver (2) || 4,532 || 12–17 |- style="background:#bfb" | 30 || May 15 || Reds || 7–0 || Rick Wise (4–2) || Tony Cloninger (1–5) || None || 3,294 || 13–17 |- style="background:#bfb" | 31 || May 16 || Giants || 3–1 || Woodie Fryman (4–1) || Mike McCormick (1–1) || None || 12,587 || 14–17 |- style="background:#fbb" | 32 || May 17 || Giants || 0–5 || Gaylord Perry (6–3) || Gary Wagner (0–3) || None || 12,514 || 14–18 |- style="background:#bfb" | 33 || May 18 || Giants || 9–8 || Turk Farrell (2–2) || Bobby Bolin (2–3) || None || 17,534 || 15–18 |- style="background:#fbb" | 34 || May 20 || @ Reds || 0–4 || Tony Cloninger (2–5) || Rick Wise (4–3) || None || 4,191 || 15–19 |- style="background:#fbb" | 35 || May 21 || @ Reds || 5–6 || Clay Carroll (3–3) || Jerry Johnson (2–4) || None || 4,811 || 15–20 |- style="background:#bfb" | 36 || May 23 || @ Braves || 6–2 || Grant Jackson (4–4) || Milt Pappas (3–3) || None || 14,868 || 16–20 |- style="background:#bfb" | 37 || May 24 || @ Braves || 8–3 || Rick Wise (5–3) || Ron Reed (5–2) || Bill Wilson (1) || 20,610 || 17–20 |- style="background:#fbb" | 38 || May 25 || @ Braves || 1–4 || George Stone (5–0) || Jerry Johnson (2–5) || Cecil Upshaw (10) || 35,172 || 17–21 |- style="background:#fbb" | 39 || May 27 ||