| 51 || June 13 || Cardinals || 3–2 || Frank Sullivan (3–7) || Larry Jackson (2–6) || None || 7,327 || 18–33 |- style="background:#bbb" | – || June 14 || Cardinals || colspan=6 | Postponed (rain); Makeup: August 29 as a traditional double-header |- style="background:#fbb" | 52 || June 15 || Cardinals || 3–6 || Ray Sadecki (5–4) || Art Mahaffey (6–6) || Bob Miller (2) || 6,789 || 18–34 |- style="background:#fbb" | 53 || June 16 || Reds || 1–4 || Ken Hunt (7–3) || John Buzhardt (2–7) || Jim Brosnan (10) || 10,508 || 18–35 |- style="background:#fbb" | 54 || June 17 || Reds || 5–10 || Bob Purkey (8–3) || Robin Roberts (1–8) || None || 5,205 || 18–36 |- style="background:#fbb" | 55 || June 18 (1) || Reds || 2–7 || Howie Nunn (2–0) || Don Ferrarese (1–3) || None || see 2nd game || 18–37 |- style="background:#fbb" | 56 || June 18 (2) || Reds || 0–10 || Jim O'Toole (6–6) || Chris Short (1–3) || None || 16,369 || 18–38 |- style="background:#fbb" | 57 || June 20 || Pirates || 2–6 || Harvey Haddix (5–2) || Art Mahaffey (6–7) || Roy Face (10) || 10,649 || 18–39 |- style="background:#bbb" | – || June 21 || Pirates || colspan=6 | Postponed (rain); Makeup: August 8 as a traditional double-header |- style="background:#fbb" | 58 || June 22 || Pirates || 1–5 || Bob Friend (8–7) || John Buzhardt (2–8) || None || 9,126 || 18–40 |- style="background:#bfb" | 59 || June 23 || @ Pirates || 12–11 || Ken Lehman (1–0) || Earl Francis (0–2) || Frank Sullivan (1) || 16,170 || 19–40 |- style="background:#bfb" | 60 || June 24 || @ Pirates || 6–2 || Chris Short (2–3) || Vinegar Bend Mizell (4–6) || Frank Sullivan (2) || 9,546 || 20–40 |- style="background:#fbb" | 61 || June 25 (1) || @ Pirates || 5–10 || Roy Face (3–3) || Jack Baldschun (0–1) || None || see 2nd game || 20–41 |- style="background:#bfb" | 62 || June 25 (2) || @ Pirates || 4–3 || Art Mahaffey (7–7) || Harvey Haddix (5–3) || Frank Sullivan (3) || 10,951 || 21–41 |- style="background:#bfb" | 63 || June 26 || Giants || 1–0 || Jim Owens (1–0) || Jack Sanford (3–5) || Dallas Green (1) || 7,872 || 22–41 |- style="background:#fbb" | 64 || June 27 ||