diff --git a/internal/handshake/qtls.go b/internal/handshake/qtls.go
index 9ce5e655c..67ed90a6a 100644
--- a/internal/handshake/qtls.go
+++ b/internal/handshake/qtls.go
@@ -51,6 +51,10 @@ func (c *clientSessionCache) Get(sessionKey string) (*qtls.ClientSessionState, b
 }
 
 func (c *clientSessionCache) Put(sessionKey string, cs *qtls.ClientSessionState) {
+	if cs == nil {
+		c.ClientSessionCache.Put(sessionKey, nil)
+		return
+	}
 	// qtls.ClientSessionState is identical to the tls.ClientSessionState.
 	// In order to allow users of quic-go to use a tls.Config,
 	// we need this workaround to use the ClientSessionCache.
diff --git a/internal/handshake/qtls_test.go b/internal/handshake/qtls_test.go
index 8a895a351..481b407dc 100644
--- a/internal/handshake/qtls_test.go
+++ b/internal/handshake/qtls_test.go
@@ -125,5 +125,14 @@ var _ = Describe("qtls.Config generation", func() {
 			_, ok := qtlsConf.ClientSessionCache.Get("raboof")
 			Expect(ok).To(BeTrue())
 		})
+
+		It("puts a nil session state", func() {
+			csc := NewMockClientSessionCache(mockCtrl)
+			tlsConf := &tls.Config{ClientSessionCache: csc}
+			qtlsConf := tlsConfigToQtlsConfig(tlsConf, nil, &mockExtensionHandler{})
+			// put something
+			csc.EXPECT().Put("foobar", nil)
+			qtlsConf.ClientSessionCache.Put("foobar", nil)
+		})
 	})
 })