diff --git a/model/renderers/gemma4.go b/model/renderers/gemma4.go
index 59133527f..4d8baa539 100644
--- a/model/renderers/gemma4.go
+++ b/model/renderers/gemma4.go
@@ -125,7 +125,7 @@ func (r *Gemma4Renderer) Render(messages []api.Message, tools []api.Tool, thinkV
 	// Generation prompt.
 	if prevMessageType != "tool_response" && prevMessageType != "tool_call" {
 		sb.WriteString("<|turn>model\n")
-		if r.emptyBlockOnNothink {
+		if r.emptyBlockOnNothink && !hasThink {
 			sb.WriteString("<|channel>thought\n<channel|>")
 		}
 	}
diff --git a/model/renderers/gemma4_reference_test.go b/model/renderers/gemma4_reference_test.go
index d65a061e4..cb5a46963 100644
--- a/model/renderers/gemma4_reference_test.go
+++ b/model/renderers/gemma4_reference_test.go
@@ -1508,6 +1508,13 @@ func TestGemma4RendererVariantsMatchExpectedGenerationPrompt(t *testing.T) {
 	}
 }
 
+func TestGemma4LargeRendererOmitsEmptyThoughtBlockWhenThinkingEnabled(t *testing.T) {
+	got, err := RenderWithRenderer("gemma4-large", []api.Message{{Role: "user", Content: "Hello"}}, nil, thinkTrue())
+	assert.NoError(t, err)
+	assert.Equal(t, "<bos><|turn>system\n<|think|>\n<turn|>\n<|turn>user\nHello<turn|>\n<|turn>model\n", got)
+	assert.NotContains(t, got, "<|channel>thought\n<channel|>")
+}
+
 func TestGemma4RendererMatchesJinja2ExpandedParity(t *testing.T) {
 	if os.Getenv("VERIFY_JINJA2") == "" {
 		t.Skip("set VERIFY_JINJA2=1 to run expanded Jinja2 parity checks")