diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index a1bf866c6..c21a8c982 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -2497,12 +2497,14 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc)
 
     ZSTD_Sequence* outSeqs = &zc->seqCollector.seqStart[zc->seqCollector.seqIndex];
     size_t i;
-    int repIdx;
+    repcodes_t updatedRepcodes;
 
     assert(zc->seqCollector.seqIndex + 1 < zc->seqCollector.maxSequences);
     /* Ensure we have enough space for last literals "sequence" */
     assert(zc->seqCollector.maxSequences >= seqStoreSeqSize + 1);
+    ZSTD_memcpy(updatedRepcodes.rep, zc->blockState.prevCBlock->rep, sizeof(repcodes_t));
     for (i = 0; i < seqStoreSeqSize; ++i) {
+        U32 rawOffset = seqStoreSeqs[i].offset - ZSTD_REP_NUM;
         outSeqs[i].litLength = seqStoreSeqs[i].litLength;
         outSeqs[i].matchLength = seqStoreSeqs[i].matchLength + MINMATCH;
         outSeqs[i].rep = 0;
@@ -2516,27 +2518,26 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc)
         }
 
         if (seqStoreSeqs[i].offset <= ZSTD_REP_NUM) {
+            /* Derive the correct offset corresponding to a repcode */
             outSeqs[i].rep = seqStoreSeqs[i].offset;
-            repIdx = (unsigned int)i - seqStoreSeqs[i].offset;
-
-            if (seqStoreSeqs[i].litLength == 0) {
-                if (seqStoreSeqs[i].offset < 3) {
-                    --repIdx;
+            if (outSeqs[i].litLength != 0) {
+                rawOffset = updatedRepcodes.rep[outSeqs[i].rep - 1];
+            } else {
+                if (outSeqs[i].rep == 3) {
+                    rawOffset = updatedRepcodes.rep[0] - 1;
                 } else {
-                    repIdx = (unsigned int)i - 1;
+                    rawOffset = updatedRepcodes.rep[outSeqs[i].rep];
                 }
             }
-            assert(repIdx >= -3);
-            outSeqs[i].offset = repIdx >= 0 ? outSeqs[repIdx].offset : repStartValue[-repIdx - 1];
-            if (outSeqs[i].rep == 3 && outSeqs[i].litLength == 0) {
-                --outSeqs[i].offset;
-            }
-        } else {
-            outSeqs[i].offset = seqStoreSeqs[i].offset - ZSTD_REP_NUM;
         }
+        outSeqs[i].offset = rawOffset;
+        /* seqStoreSeqs[i].offset == offCode+1, and ZSTD_updateRep() expects offCode
+           so we provide seqStoreSeqs[i].offset - 1 */
+        updatedRepcodes = ZSTD_updateRep(updatedRepcodes.rep,
+                                         seqStoreSeqs[i].offset - 1,
+                                         seqStoreSeqs[i].litLength == 0);
         literalsRead += outSeqs[i].litLength;
     }
-
     /* Insert last literals (if any exist) in the block as a sequence with ml == off == 0.
      * If there are no last literals, then we'll emit (of: 0, ml: 0, ll: 0), which is a marker
      * for the block boundary, according to the API.
@@ -2546,7 +2547,6 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc)
     outSeqs[i].litLength = (U32)lastLLSize;
     outSeqs[i].matchLength = outSeqs[i].offset = outSeqs[i].rep = 0;
     seqStoreSeqSize++;
-
     zc->seqCollector.seqIndex += seqStoreSeqSize;
 }
 
diff --git a/tests/fuzzer.c b/tests/fuzzer.c
index 65e442093..2afd10935 100644
--- a/tests/fuzzer.c
+++ b/tests/fuzzer.c
@@ -2721,9 +2721,9 @@ static int basicUnitTests(U32 const seed, double compressibility)
 
         if (seqs == NULL) goto _output_error;
         assert(cctx != NULL);
-
+        ZSTD_CCtx_setParameter(cctx, ZSTD_c_compressionLevel, 19);
         /* Populate src with random data */
-        RDG_genBuffer(CNBuffer, srcSize, compressibility, 0., seed);
+        RDG_genBuffer(CNBuffer, srcSize, compressibility, 0.5, seed);
 
         /* Test with block delimiters roundtrip */
         seqsSize = ZSTD_generateSequences(cctx, seqs, srcSize, src, srcSize);