diff --git a/python3/httplib2/__init__.py b/python3/httplib2/__init__.py
index 6467c790..00a45ab0 100644
--- a/python3/httplib2/__init__.py
+++ b/python3/httplib2/__init__.py
@@ -1284,7 +1284,7 @@ def __init__(
 
     def connect(self):
         """Connect to a host on a given (SSL) port."""
-        if self.proxy_info and self.proxy_info.isgood():
+        if self.proxy_info and self.proxy_info.isgood() and self.proxy_info.applies_to(self.host):
             use_proxy = True
             proxy_type, proxy_host, proxy_port, proxy_rdns, proxy_user, proxy_pass, proxy_headers = (
                 self.proxy_info.astuple()
diff --git a/tests/test_proxy.py b/tests/test_proxy.py
index 4ec8aea9..61d9502b 100644
--- a/tests/test_proxy.py
+++ b/tests/test_proxy.py
@@ -36,16 +36,18 @@ def test_from_url_ident():
     assert pi.proxy_pass == "fish"
 
 
-def test_from_env():
-    os.environ["http_proxy"] = "http://myproxy.example.com:8080"
+def test_from_env(monkeypatch):
+    assert os.environ.get("http_proxy") is None
+    monkeypatch.setenv("http_proxy", "http://myproxy.example.com:8080")
     pi = httplib2.proxy_info_from_environment()
     assert pi.proxy_host == "myproxy.example.com"
     assert pi.proxy_port == 8080
 
 
-def test_from_env_https():
-    os.environ["http_proxy"] = "http://myproxy.example.com:80"
-    os.environ["https_proxy"] = "http://myproxy.example.com:81"
+def test_from_env_https(monkeypatch):
+    assert os.environ.get("http_proxy") is None
+    monkeypatch.setenv("http_proxy", "http://myproxy.example.com:80")
+    monkeypatch.setenv("https_proxy", "http://myproxy.example.com:81")
     pi = httplib2.proxy_info_from_environment("https")
     assert pi.proxy_host == "myproxy.example.com"
     assert pi.proxy_port == 81
@@ -57,10 +59,10 @@ def test_from_env_none():
     assert pi is None
 
 
-def test_applies_to():
-    os.environ["http_proxy"] = "http://myproxy.example.com:80"
-    os.environ["https_proxy"] = "http://myproxy.example.com:81"
-    os.environ["no_proxy"] = "localhost,example.com,.wildcard"
+def test_applies_to(monkeypatch):
+    monkeypatch.setenv("http_proxy", "http://myproxy.example.com:80")
+    monkeypatch.setenv("https_proxy", "http://myproxy.example.com:81")
+    monkeypatch.setenv("no_proxy", "localhost,example.com,.wildcard")
     pi = httplib2.proxy_info_from_environment()
     assert not pi.applies_to("localhost")
     assert pi.applies_to("www.google.com")
@@ -71,18 +73,18 @@ def test_applies_to():
     assert not pi.applies_to("pub.sub.wildcard")
 
 
-def test_noproxy_trailing_comma():
-    os.environ["http_proxy"] = "http://myproxy.example.com:80"
-    os.environ["no_proxy"] = "localhost,other.host,"
+def test_noproxy_trailing_comma(monkeypatch):
+    monkeypatch.setenv("http_proxy", "http://myproxy.example.com:80")
+    monkeypatch.setenv("no_proxy", "localhost,other.host,")
     pi = httplib2.proxy_info_from_environment()
     assert not pi.applies_to("localhost")
     assert not pi.applies_to("other.host")
     assert pi.applies_to("example.domain")
 
 
-def test_noproxy_star():
-    os.environ["http_proxy"] = "http://myproxy.example.com:80"
-    os.environ["NO_PROXY"] = "*"
+def test_noproxy_star(monkeypatch):
+    monkeypatch.setenv("http_proxy", "http://myproxy.example.com:80")
+    monkeypatch.setenv("NO_PROXY", "*")
     pi = httplib2.proxy_info_from_environment()
     for host in ("localhost", "169.254.38.192", "www.google.com"):
         assert not pi.applies_to(host)
@@ -171,3 +173,37 @@ def proxy_conn(client, tick):
         http = httplib2.Http(proxy_info=proxy_info)
         with tests.assert_raises(httplib2.socks.Socks5AuthError):
             http.request(uri, "GET")
+
+
+def test_functional_noproxy_star_http(monkeypatch):
+    def handler(request):
+        if request.method == "CONNECT":
+            return tests.http_response_bytes(
+                status="400 Expected direct", headers={"connection": "close"},
+            )
+        return tests.http_response_bytes()
+
+    with tests.server_request(handler) as uri:
+        uri_parsed = urllib.parse.urlparse(uri)
+        monkeypatch.setenv("http_proxy", uri)
+        monkeypatch.setenv("no_proxy", "*")
+        http = httplib2.Http()
+        response, _ = http.request(uri, "GET")
+        assert response.status == 200
+
+
+def test_functional_noproxy_star_https(monkeypatch):
+    def handler(request):
+        if request.method == "CONNECT":
+            return tests.http_response_bytes(
+                status="400 Expected direct", headers={"connection": "close"},
+            )
+        return tests.http_response_bytes()
+
+    with tests.server_request(handler, tls=True) as uri:
+        uri_parsed = urllib.parse.urlparse(uri)
+        monkeypatch.setenv("https_proxy", uri)
+        monkeypatch.setenv("no_proxy", "*")
+        http = httplib2.Http(ca_certs=tests.CA_CERTS)
+        response, _ = http.request(uri, "GET")
+        assert response.status == 200