diff --git a/src/common/serialize_series.go b/src/common/serialize_series.go
index 6a0649a15ca..232005e4493 100644
--- a/src/common/serialize_series.go
+++ b/src/common/serialize_series.go
@@ -66,6 +66,9 @@ func ConvertToDataStoreSeries(s ApiSeries, precision TimePrecision) (*protocol.S
 
 			value := point[idx]
 			if field == "time" {
+				if timestamp != nil {
+					return nil, fmt.Errorf("duplicate time field %T (%v)", value, value)
+				}
 				switch x := value.(type) {
 				case json.Number:
 					f, err := x.Float64()
@@ -89,6 +92,9 @@ func ConvertToDataStoreSeries(s ApiSeries, precision TimePrecision) (*protocol.S
 			}
 
 			if field == "sequence_number" {
+				if sequence != nil {
+					return nil, fmt.Errorf("duplicate sequence_number field %T (%v)", value, value)
+				}
 				switch x := value.(type) {
 				case json.Number:
 					f, err := x.Float64()
diff --git a/src/common/serialize_series_test.go b/src/common/serialize_series_test.go
new file mode 100644
index 00000000000..c1bc453387b
--- /dev/null
+++ b/src/common/serialize_series_test.go
@@ -0,0 +1,63 @@
+package common
+
+import (
+	"bytes"
+	"encoding/json"
+	. "launchpad.net/gocheck"
+	"testing"
+)
+
+// Hook up gocheck into the gotest runner.
+func Test(t *testing.T) {
+	TestingT(t)
+}
+
+type SerializeSeriesSuite struct{}
+
+var _ = Suite(&SerializeSeriesSuite{})
+
+func (self *SerializeSeriesSuite) TestValidApiSeries(c *C) {
+	serializedSeries := serializeSeriesJson([]byte(`
+  {
+    "name" : "hd_used",
+    "columns" : ["time", "value", "host", "mount"],
+    "points" : [
+      [1403761091094, 23.2, "serverA", "/mnt"]
+    ]
+  }`))
+	_, err := ConvertToDataStoreSeries(serializedSeries, MillisecondPrecision)
+	c.Assert(err, IsNil)
+}
+
+func (self *SerializeSeriesSuite) TestDuplicateTimeApiSeries(c *C) {
+	serializedSeries := serializeSeriesJson([]byte(`
+  {
+    "name" : "hd_used",
+    "columns" : ["time", "value", "time", "host", "mount"],
+    "points" : [
+      [1403761091094, 23.2, 1403761091094, "serverA", "/mnt"]
+    ]
+  }`))
+	_, err := ConvertToDataStoreSeries(serializedSeries, MillisecondPrecision)
+	c.Assert(err, Not(IsNil))
+}
+
+func (self *SerializeSeriesSuite) TestDuplicateSequenceNumberApiSeries(c *C) {
+	serializedSeries := serializeSeriesJson([]byte(`
+  {
+    "name" : "hd_used",
+    "columns" : ["time", "sequence_number", "sequence_number", "host", "mount"],
+    "points" : [
+      [1403761091094, 100, 100, "serverA", "/mnt"]
+    ]
+  }`))
+	_, err := ConvertToDataStoreSeries(serializedSeries, MillisecondPrecision)
+	c.Assert(err, Not(IsNil))
+}
+
+func serializeSeriesJson(jsonData []byte) (serializedSeries *SerializedSeries) {
+	decoder := json.NewDecoder(bytes.NewBuffer(jsonData))
+	decoder.UseNumber()
+	decoder.Decode(&serializedSeries)
+	return
+}