diff --git a/src/common/utils.h b/src/common/utils.h
index 158f43c11..f55fd5848 100644
--- a/src/common/utils.h
+++ b/src/common/utils.h
@@ -36,6 +36,8 @@ typedef struct {
     struct timeval end_time;
     struct timeval pkt_ts_delta;
     struct timeval last_print;
+    struct timeval first_packet_sent_wall_time;
+    struct timeval first_packet_pcap_timestamp;
     COUNTER flow_non_flow_packets;
     COUNTER flows;
     COUNTER flows_unique;
diff --git a/src/send_packets.c b/src/send_packets.c
index 1f39dd21a..8638db4b5 100644
--- a/src/send_packets.c
+++ b/src/send_packets.c
@@ -588,18 +588,26 @@ send_packets(tcpreplay_t *ctx, pcap_t *pcap, int idx)
             ctx->skip_packets = 0;
 
             if (options->speed.mode == speed_multiplier) {
+                if(!timerisset(&stats->first_packet_sent_wall_time))
+                {
+                    /* We're sending the first packet, so we have an absolute time reference. */
+                    TIMEVAL_SET(&stats->first_packet_sent_wall_time, &now);
+                    TIMEVAL_SET(&stats->first_packet_pcap_timestamp, &pkthdr.ts);
+                }
+
                 if (!timerisset(&last_pkt_ts)) {
                     TIMEVAL_SET(&last_pkt_ts, &pkthdr.ts);
                 } else if (timercmp(&pkthdr.ts, &last_pkt_ts, >)) {
                     struct timeval delta;
 
-                    timersub(&pkthdr.ts, &last_pkt_ts, &delta);
-                    timeradd(&stats->pkt_ts_delta, &delta, &stats->pkt_ts_delta);
+                    /* pkt_ts_delta is the packet time stamp difference since the first packet */
+                    timersub(&pkthdr.ts, &stats->first_packet_pcap_timestamp, &stats->pkt_ts_delta);
+
+                    /* time_delta is the wall time difference since sending the first packet */
+                    timersub(&now, &stats->first_packet_sent_wall_time, &stats->time_delta);
+
                     TIMEVAL_SET(&last_pkt_ts, &pkthdr.ts);
                 }
-
-                if (!timerisset(&stats->time_delta))
-                    TIMEVAL_SET(&stats->pkt_ts_delta, &stats->pkt_ts_delta);
             }
 
             if (!top_speed) {