June 16 || @ Reds || 0–5 || Clay Carroll (4–1) || Dick Ruthven (2–4) || None || 30,006 || 33–29 |- style="background:#bfb" | 63 || June 17 || Astros || 7–5 || Wayne Twitchell (1–1) || Claude Osteen (5–7) || None || 18,289 || 34–29 |- style="background:#fbb" | 64 || June 18 || Astros || 0–1 || Mike Cosgrove (2–0) || Ron Schueler (3–8) || None || 14,165 || 34–30 |- style="background:#bfb" | 65 || June 19 || Astros || 5–4 || Jim Lonborg (9–5) || Tom Griffin (7–3) || Mac Scarce (4) || 17,161 || 35–30 |- style="background:#fbb" | 66 || June 20 || Mets || 1–2 || Jerry Koosman (7–4) || Dick Ruthven (2–5) || None || 22,210 || 35–31 |- style="background:#fbb" | 67 || June 21 || Mets || 1–3 || Tom Seaver (4–6) || Steve Carlton (9–5) || Tug McGraw (2) || 28,262 || 35–32 |- style="background:#bfb" | 68 || June 22 (1) || Mets || 5–2 || Ron Schueler (4–8) || Harry Parker (1–7) || None || see 2nd game || 36–32 |- style="background:#bfb" | 69 || June 22 (2) || Mets || 8–5 || Wayne Twitchell (2–1) || George Stone (2–6) || Jesús Hernáiz (1) || 51,197 || 37–32 |- style="background:#bbb" | – || June 23 || Mets || colspan=6 | Postponed (rain); Makeup: September 25 as a traditional double-header |- style="background:#bfb" | 70 || June 24 || @ Expos || 8–2 || Jim Lonborg (10–5) || Mike Torrez (7–5) || None || Mike Torrez || 38–32 |- style="background:#fbb" | 71 || June 25 || @ Expos || 0–5 || Steve Renko (5–7) || Dick Ruthven (2–6) || None || 18,122 || 38–33 |- style="background:#fbb" | 72 || June 26 || @ Expos || 0–2 || Steve Rogers (8–8) || Steve Carlton (9–6) || None || 16,108 || 38–34 |- style="background:#bbb" | – || June 28 || @ Pirates || colspan=6 | Postponed (rain); Makeup: June 30 as a traditional double-header |- style="background:#fbb" | 73 || June 29 || @ Pirates || 3–6 || Jerry Reuss (7–5) || Jim Lonborg (10–6) || None || 15,839 || 38–35 |- style="background:#fbb" | 74 || June 30 (1) || @ Pirates || 8–11 || Ken Brett (10–4) || Steve Carlton (9–7) || None || see 2nd game || 38–36 |- style="background:#fbb" | 75 || June 30 (2) || @ Pirates || 2–3 || Bruce Kison (3–3)