diff --git a/quic/core/quic_sent_packet_manager_test.cc b/quic/core/quic_sent_packet_manager_test.cc
index 0ac8df7..a54b610 100644
--- a/quic/core/quic_sent_packet_manager_test.cc
+++ b/quic/core/quic_sent_packet_manager_test.cc
@@ -129,7 +129,8 @@
     EXPECT_FALSE(manager_.unacked_packets().empty());
     EXPECT_EQ(QuicPacketNumber(packets[0]), manager_.GetLeastUnacked());
     for (size_t i = 0; i < num_packets; ++i) {
-      EXPECT_TRUE(QuicSentPacketManagerPeer::IsUnacked(&manager_, packets[i]))
+      EXPECT_TRUE(
+          manager_.unacked_packets().IsUnacked(QuicPacketNumber(packets[i])))
           << packets[i];
     }
   }
@@ -1259,8 +1260,8 @@
   manager_.RetransmitUnackedPackets(ALL_UNACKED_RETRANSMISSION);
   if (manager_.session_decides_what_to_write()) {
     // Both packets 1 and 2 are unackable.
-    EXPECT_FALSE(QuicSentPacketManagerPeer::IsUnacked(&manager_, 1));
-    EXPECT_FALSE(QuicSentPacketManagerPeer::IsUnacked(&manager_, 2));
+    EXPECT_FALSE(manager_.unacked_packets().IsUnacked(QuicPacketNumber(1)));
+    EXPECT_FALSE(manager_.unacked_packets().IsUnacked(QuicPacketNumber(2)));
   } else {
     // Packet 2 is useful because it does not get retransmitted and still has
     // retransmittable frames.
diff --git a/quic/test_tools/quic_sent_packet_manager_peer.cc b/quic/test_tools/quic_sent_packet_manager_peer.cc
index 41b2c43..ee13830 100644
--- a/quic/test_tools/quic_sent_packet_manager_peer.cc
+++ b/quic/test_tools/quic_sent_packet_manager_peer.cc
@@ -194,14 +194,6 @@
 }
 
 // static
-bool QuicSentPacketManagerPeer::IsUnacked(
-    QuicSentPacketManager* sent_packet_manager,
-    uint64_t packet_number) {
-  return sent_packet_manager->unacked_packets_.IsUnacked(
-      QuicPacketNumber(packet_number));
-}
-
-// static
 bool QuicSentPacketManagerPeer::HasRetransmittableFrames(
     QuicSentPacketManager* sent_packet_manager,
     uint64_t packet_number) {
diff --git a/quic/test_tools/quic_sent_packet_manager_peer.h b/quic/test_tools/quic_sent_packet_manager_peer.h
index bab5836..7a852a0 100644
--- a/quic/test_tools/quic_sent_packet_manager_peer.h
+++ b/quic/test_tools/quic_sent_packet_manager_peer.h
@@ -88,9 +88,6 @@
 
   static bool UsingPacing(const QuicSentPacketManager* sent_packet_manager);
 
-  static bool IsUnacked(QuicSentPacketManager* sent_packet_manager,
-                        uint64_t packet_number);
-
   static bool HasRetransmittableFrames(
       QuicSentPacketManager* sent_packet_manager,
       uint64_t packet_number);