diff --git a/src/traces/sankey/render.js b/src/traces/sankey/render.js
index 3ed5be40915..b31a0b6911f 100644
--- a/src/traces/sankey/render.js
+++ b/src/traces/sankey/render.js
@@ -155,8 +155,8 @@ function linkModel(uniqueKeys, d, l) {
     var tc = tinycolor(l.color);
     var basicKey = l.source.label + '|' + l.target.label;
     var foundKey = uniqueKeys[basicKey];
-    uniqueKeys[basicKey] = (foundKey === void(0) ? foundKey : 0) + 1;
-    var key = basicKey + (foundKey === void(0) ? '' : '__' + foundKey);
+    uniqueKeys[basicKey] = (foundKey || 0) + 1;
+    var key = basicKey + '__' + uniqueKeys[basicKey];
 
     // for event data
     l.trace = d.trace;
@@ -186,8 +186,8 @@ function nodeModel(uniqueKeys, d, n) {
 
     var basicKey = n.label;
     var foundKey = uniqueKeys[basicKey];
-    uniqueKeys[basicKey] = (foundKey === void(0) ? foundKey : 0) + 1;
-    var key = basicKey + (foundKey === void(0) ? '' : '__' + foundKey);
+    uniqueKeys[basicKey] = (foundKey || 0) + 1;
+    var key = basicKey + '__' + uniqueKeys[basicKey];
 
     // for event data
     n.trace = d.trace;
diff --git a/test/image/baselines/sankey_energy.png b/test/image/baselines/sankey_energy.png
index d057a2b49a3..3ca3c968929 100644
Binary files a/test/image/baselines/sankey_energy.png and b/test/image/baselines/sankey_energy.png differ
diff --git a/test/image/mocks/sankey_energy.json b/test/image/mocks/sankey_energy.json
index b70e8eb450e..f7c25259b69 100644
--- a/test/image/mocks/sankey_energy.json
+++ b/test/image/mocks/sankey_energy.json
@@ -192,7 +192,9 @@
                     44,
                     45,
                     46,
-                    47
+                    47,
+                    35,
+                    35
                 ],
                 "target": [
                     1,
@@ -263,7 +265,9 @@
                     15,
                     1,
                     15,
-                    15
+                    15,
+                    26,
+                    26
                 ],
                 "value": [
                     124.729,
@@ -313,7 +317,7 @@
                     14.375,
                     122.952,
                     500,
-                    339.978,
+                    139.978,
                     504.287,
                     107.703,
                     611.99,
@@ -334,7 +338,9 @@
                     9.452,
                     182.01,
                     19.013,
-                    289.366
+                    289.366,
+                    100,
+                    100
                 ],
                 "color": [
                     "rgba(0,0,96,0.2)",
@@ -405,7 +411,9 @@
                     "rgba(0,0,96,0.2)",
                     "rgba(0,0,96,0.2)",
                     "rgba(0,0,96,0.2)",
-                    "rgba(0,0,96,0.2)"
+                    "rgba(0,0,96,0.2)",
+                    "lightgreen",
+                    "goldenrod"
                 ],
                 "label": [
                     "stream 1",
@@ -476,6 +484,8 @@
                     "",
                     "",
                     "",
+                    "",
+                    "",
                     ""
                 ]
             }