diff --git a/ackhandler/sent_packet_handler.go b/ackhandler/sent_packet_handler.go
index a4b606061..48ad713b1 100644
--- a/ackhandler/sent_packet_handler.go
+++ b/ackhandler/sent_packet_handler.go
@@ -99,10 +99,6 @@ func (h *sentPacketHandler) SetHandshakeComplete() {
 }
 
 func (h *sentPacketHandler) SentPacket(packet *Packet) error {
-	if packet.PacketNumber <= h.lastSentPacketNumber {
-		return errors.New("Already sent a packet with a higher packet number")
-	}
-
 	if protocol.PacketNumber(len(h.retransmissionQueue)+h.packetHistory.Len()+1) > protocol.MaxTrackedSentPackets {
 		return errors.New("Too many outstanding non-acked and non-retransmitted packets")
 	}
diff --git a/ackhandler/sent_packet_handler_test.go b/ackhandler/sent_packet_handler_test.go
index dcfbd16da..90e8b65bb 100644
--- a/ackhandler/sent_packet_handler_test.go
+++ b/ackhandler/sent_packet_handler_test.go
@@ -124,31 +124,6 @@ var _ = Describe("SentPacketHandler", func() {
 			Expect(handler.skippedPackets).To(BeEmpty())
 		})
 
-		It("rejects packets with the same packet number", func() {
-			packet1 := Packet{PacketNumber: 1, Frames: []wire.Frame{&streamFrame}, Length: 1}
-			packet2 := Packet{PacketNumber: 1, Frames: []wire.Frame{&streamFrame}, Length: 2}
-			err := handler.SentPacket(&packet1)
-			Expect(err).ToNot(HaveOccurred())
-			err = handler.SentPacket(&packet2)
-			Expect(err).To(MatchError("Already sent a packet with a higher packet number"))
-			Expect(handler.lastSentPacketNumber).To(Equal(protocol.PacketNumber(1)))
-			Expect(handler.packetHistory.Front().Value.PacketNumber).To(Equal(protocol.PacketNumber(1)))
-			Expect(handler.bytesInFlight).To(Equal(protocol.ByteCount(1)))
-			Expect(handler.skippedPackets).To(BeEmpty())
-		})
-
-		It("rejects packets with decreasing packet number", func() {
-			packet1 := Packet{PacketNumber: 2, Frames: []wire.Frame{&streamFrame}, Length: 1}
-			packet2 := Packet{PacketNumber: 1, Frames: []wire.Frame{&streamFrame}, Length: 2}
-			err := handler.SentPacket(&packet1)
-			Expect(err).ToNot(HaveOccurred())
-			err = handler.SentPacket(&packet2)
-			Expect(err).To(MatchError("Already sent a packet with a higher packet number"))
-			Expect(handler.lastSentPacketNumber).To(Equal(protocol.PacketNumber(2)))
-			Expect(handler.packetHistory.Front().Value.PacketNumber).To(Equal(protocol.PacketNumber(2)))
-			Expect(handler.bytesInFlight).To(Equal(protocol.ByteCount(1)))
-		})
-
 		It("stores the sent time", func() {
 			packet := Packet{PacketNumber: 1, Frames: []wire.Frame{&streamFrame}, Length: 1}
 			err := handler.SentPacket(&packet)