diff --git a/engine/src/main/java/io/seldon/engine/predictors/PredictiveUnitBean.java b/engine/src/main/java/io/seldon/engine/predictors/PredictiveUnitBean.java
index 37bd186c9a..c6167f2809 100644
--- a/engine/src/main/java/io/seldon/engine/predictors/PredictiveUnitBean.java
+++ b/engine/src/main/java/io/seldon/engine/predictors/PredictiveUnitBean.java
@@ -87,7 +87,11 @@ private void addMetrics(SeldonMessage msg,PredictiveUnitState state,Map<String,L
 		if (msg.hasMeta())
 		{
 			addCustomMetrics(msg.getMeta().getMetricsList(),state);
-			metrics.put(state.name,msg.getMeta().getMetricsList());
+			if (!metrics.containsKey(state.name))
+				metrics.putIfAbsent(state.name,new ArrayList<>());
+			List<Metric> current = metrics.get(state.name);
+			current.addAll(msg.getMeta().getMetricsList());
+			metrics.put(state.name,current);
 		}
 	}
 	
diff --git a/engine/src/test/java/io/seldon/engine/api/rest/TestRestClientControllerExternalGraphs.java b/engine/src/test/java/io/seldon/engine/api/rest/TestRestClientControllerExternalGraphs.java
index 6ad0d81944..bb1a8b8339 100644
--- a/engine/src/test/java/io/seldon/engine/api/rest/TestRestClientControllerExternalGraphs.java
+++ b/engine/src/test/java/io/seldon/engine/api/rest/TestRestClientControllerExternalGraphs.java
@@ -326,7 +326,8 @@ public void testTransformOutputMetrics() throws Exception
     public void testRouterMetrics() throws Exception
     {
     	String jsonStr = readFile("src/test/resources/router_simple.json",StandardCharsets.UTF_8);
-    	String responseStr = readFile("src/test/resources/router_response.json",StandardCharsets.UTF_8);
+    	String responseStrRouter = readFile("src/test/resources/router_response.json",StandardCharsets.UTF_8);
+    	String responseStrModel = readFile("src/test/resources/router_model_response.json",StandardCharsets.UTF_8);    	
     	PredictorSpec.Builder PredictorSpecBuilder = PredictorSpec.newBuilder();
     	updateMessageBuilderFromJson(PredictorSpecBuilder, jsonStr);
     	PredictorSpec predictorSpec = PredictorSpecBuilder.build();
@@ -337,9 +338,19 @@ public void testRouterMetrics() throws Exception
     	enginePredictor.setPredictorSpec(predictorSpec);
     	
     	
-    	ResponseEntity<String> httpResponse = new ResponseEntity<String>(responseStr, null, HttpStatus.OK);
+    	ResponseEntity<String> httpResponse1 = new ResponseEntity<String>(responseStrRouter, null, HttpStatus.OK);
+    	ResponseEntity<String> httpResponse2 = new ResponseEntity<String>(responseStrModel, null, HttpStatus.OK);
     	Mockito.when(restTemplate.postForEntity(Matchers.<URI>any(), Matchers.<HttpEntity<MultiValueMap<String, String>>>any(), Matchers.<Class<String>>any()))
-    		.thenReturn(httpResponse);
+		.thenAnswer(new Answer<ResponseEntity<String>>() {
+		    private int count = 0;
+
+		    public ResponseEntity<String> answer(InvocationOnMock invocation) {
+		    	count++;
+		        if (count == 1)
+		            return httpResponse1;
+
+		        return httpResponse2;
+		    }});
     	internalPredictionService.setRestTemplate(restTemplate);
     	
     	MvcResult res = mvc.perform(MockMvcRequestBuilders.post("/api/v0.1/predictions")
@@ -357,23 +368,37 @@ public void testRouterMetrics() throws Exception
 	    // Check for returned metrics
 	    Assert.assertEquals("COUNTER",seldonMessage.getMeta().getMetrics(0).getType().toString());
 	    Assert.assertEquals(1.0F,seldonMessage.getMeta().getMetrics(0).getValue(),0.0);
-	    Assert.assertEquals("mycounter",seldonMessage.getMeta().getMetrics(0).getKey());
+	    Assert.assertEquals("myroutercounter",seldonMessage.getMeta().getMetrics(0).getKey());
 
 	    Assert.assertEquals("GAUGE",seldonMessage.getMeta().getMetrics(1).getType().toString());
 	    Assert.assertEquals(22.0F,seldonMessage.getMeta().getMetrics(1).getValue(),0.0);
-	    Assert.assertEquals("mygauge",seldonMessage.getMeta().getMetrics(1).getKey());
+	    Assert.assertEquals("myroutergauge",seldonMessage.getMeta().getMetrics(1).getKey());
 
 	    Assert.assertEquals("TIMER",seldonMessage.getMeta().getMetrics(2).getType().toString());
 	    Assert.assertEquals(1.0F,seldonMessage.getMeta().getMetrics(2).getValue(),0.0);
-	    Assert.assertEquals("mytimer",seldonMessage.getMeta().getMetrics(2).getKey());
+	    Assert.assertEquals("myroutertimer",seldonMessage.getMeta().getMetrics(2).getKey());
+	    
+	    Assert.assertEquals("COUNTER",seldonMessage.getMeta().getMetrics(3).getType().toString());
+	    Assert.assertEquals(1.0F,seldonMessage.getMeta().getMetrics(3).getValue(),0.0);
+	    Assert.assertEquals("myroutermodelcounter",seldonMessage.getMeta().getMetrics(3).getKey());
+
+	    Assert.assertEquals("GAUGE",seldonMessage.getMeta().getMetrics(4).getType().toString());
+	    Assert.assertEquals(22.0F,seldonMessage.getMeta().getMetrics(4).getValue(),0.0);
+	    Assert.assertEquals("myroutermodelgauge",seldonMessage.getMeta().getMetrics(4).getKey());
+
+	    Assert.assertEquals("TIMER",seldonMessage.getMeta().getMetrics(5).getType().toString());
+	    Assert.assertEquals(1.0F,seldonMessage.getMeta().getMetrics(5).getValue(),0.0);
+	    Assert.assertEquals("myroutermodeltimer",seldonMessage.getMeta().getMetrics(5).getKey());
 
 	    // Check prometheus endpoint for metric
 	    MvcResult res2 = mvc.perform(MockMvcRequestBuilders.get("/prometheus")).andReturn();
 	    Assert.assertEquals(200, res2.getResponse().getStatus());
 	    response = res2.getResponse().getContentAsString();
     	System.out.println(response);
-	    Assert.assertTrue(response.indexOf("mycounter_total{deployment_name=\"None\",model_image=\"seldonio/router\",model_name=\"router\",model_version=\"0.6\",mytag1=\"mytagval1\",predictor_name=\"fx-market-predictor\",predictor_version=\"unknown\",} 1.0")>-1);
-	    Assert.assertTrue(response.indexOf("mytimer_seconds_count{deployment_name=\"None\",model_image=\"seldonio/router\",model_name=\"router\",model_version=\"0.6\",predictor_name=\"fx-market-predictor\",predictor_version=\"unknown\",} 1.0")>-1);
+	    Assert.assertTrue(response.indexOf("myroutercounter_total{deployment_name=\"None\",model_image=\"seldonio/router\",model_name=\"router\",model_version=\"0.6\",mytag1=\"mytagval1\",predictor_name=\"fx-market-predictor\",predictor_version=\"unknown\",} 1.0")>-1);
+	    Assert.assertTrue(response.indexOf("myroutertimer_seconds_count{deployment_name=\"None\",model_image=\"seldonio/router\",model_name=\"router\",model_version=\"0.6\",predictor_name=\"fx-market-predictor\",predictor_version=\"unknown\",} 1.0")>-1);
+	    Assert.assertTrue(response.indexOf("myroutermodelcounter_total{deployment_name=\"None\",model_image=\"seldonio/model\",model_name=\"model\",model_version=\"0.6\",mytag1=\"mytagval1\",predictor_name=\"fx-market-predictor\",predictor_version=\"unknown\",} 1.0")>-1);
+	    Assert.assertTrue(response.indexOf("myroutermodeltimer_seconds_count{deployment_name=\"None\",model_image=\"seldonio/model\",model_name=\"model\",model_version=\"0.6\",predictor_name=\"fx-market-predictor\",predictor_version=\"unknown\",} 1.0")>-1);
 
     }
     
diff --git a/engine/src/test/resources/router_model_response.json b/engine/src/test/resources/router_model_response.json
new file mode 100644
index 0000000000..dbdf9d148e
--- /dev/null
+++ b/engine/src/test/resources/router_model_response.json
@@ -0,0 +1,30 @@
+{
+	"meta": {
+		"metrics": [
+			{
+				"type": "COUNTER",
+				"key": "myroutermodelcounter",
+				"value": 1.0,
+				"tags": {"mytag1":"mytagval1"}
+			},
+			{
+				"type": "GAUGE",
+				"key": "myroutermodelgauge",
+				"value": 22.0
+			},
+			{
+				"type": "TIMER",
+				"key": "myroutermodeltimer",
+				"value": 1.0
+			}
+		]
+	},
+	"data": {
+		"ndarray": [
+			[
+				1,
+				2
+			]
+		]
+	}
+}
diff --git a/engine/src/test/resources/router_response.json b/engine/src/test/resources/router_response.json
index cd6c08ffb5..2d066dcaaf 100644
--- a/engine/src/test/resources/router_response.json
+++ b/engine/src/test/resources/router_response.json
@@ -3,18 +3,18 @@
 		"metrics": [
 			{
 				"type": "COUNTER",
-				"key": "mycounter",
+				"key": "myroutercounter",
 				"value": 1.0,
 				"tags": {"mytag1":"mytagval1"}
 			},
 			{
 				"type": "GAUGE",
-				"key": "mygauge",
+				"key": "myroutergauge",
 				"value": 22.0
 			},
 			{
 				"type": "TIMER",
-				"key": "mytimer",
+				"key": "myroutertimer",
 				"value": 1.0
 			}
 		]