Short (4–3) || Gerry Arrigo (1) || 12,438 || 12–12 |- style="background:#fbb" | 25 || May 12 || Reds || 3–4 || Sammy Ellis (5–0) || Ray Culp (1–2) || Jim O'Toole (1) || 12,237 || 12–13 |- style="background:#bfb" | 26 || May 13 || Reds || 7–6 (10) || Jack Baldschun (3–0) || Jim Duffalo (0–2) || None || 10,573 || 13–13 |- style="background:#bfb" | 27 || May 14 || Braves || 5–2 || Art Mahaffey (2–0) || Billy O'Dell (1–2) || None || 19,629 || 14–13 |- style="background:#bfb" | 28 || May 15 || Braves || 6–4 || Jim Bunning (3–3) || Wade Blasingame (2–4) || Jack Baldschun (4) || 8,794 || 15–13 |- style="background:#fbb" | 29 || May 16 || Braves || 6–8 (10) || Billy O'Dell (2–2) || Jack Baldschun (3–1) || Wade Blasingame (1) || 16,632 || 15–14 |- style="background:#bfb" | 30 || May 17 || @ Cardinals || 2–1 || Bo Belinsky (1–2) || Curt Simmons (1–5) || None || 10,748 || 16–14 |- style="background:#fbb" | 31 || May 18 || @ Cardinals || 2–8 || Ray Sadecki (1–4) || Art Mahaffey (2–1) || None || 8,593 || 16–15 |- style="background:#fbb" | 32 || May 19 || @ Cardinals || 6–7 || Bob Purkey (2–3) || Ed Roebuck (1–2) || None || 18,660 || 16–16 |- style="background:#fbb" | 33 || May 20 || @ Cardinals || 2–12 || Bob Gibson (8–0) || Chris Short (4–4) || None || 13,741 || 16–17 |- style="background:#fbb" | 34 || May 21 || @ Reds || 5–6 || Joey Jay (2–1) || Art Mahaffey (2–2) || None || 14,263 || 16–18 |- style="background:#fbb" | 35 || May 22 || @ Reds || 4–9 || Joe Nuxhall (1–1) || Bo Belinsky (1–3) || Gerry Arrigo (2) || 21,296 || 16–19 |- style="background:#bfb" | 36 || May 23 || @ Reds || 4–3 (10) || Ed Roebuck (2–2) || Gerry Arrigo (1–1) || None || 14,942 || 17–19 |- style="background:#fbb" | 37 || May 24 (1) || Mets || 2–6 || Warren Spahn (4–4) || Jim Bunning (3–4) || None || see 2nd game || 17–20 |- style="background:#fbb" | 38 || May 24 (2) || Mets || 1–4 || Frank Lary (1–0) || Chris Short (4–5) || Tug McGraw (1) || || 17–21 |- style="background:#bfb" | 39 || May 25 || Mets || 10–3 || Ray Herbert (2–2) || Al