diff --git a/common/speculative.cpp b/common/speculative.cpp
index 01c7ee41b87..bd34c27e545 100644
--- a/common/speculative.cpp
+++ b/common/speculative.cpp
@@ -1096,6 +1096,16 @@ struct common_speculative_impl_draft_dflash : public common_speculative_impl {
 
         const int32_t n_ubatch = (int32_t) llama_n_ubatch(ctx_dft);
 
+        // The target context may advance over a vision chunk using positions that the
+        // independent DFlash context cannot reproduce exactly. Keep the draft in its
+        // own consecutive position space so a later decode always satisfies the
+        // one-axis RoPE invariant (Y = X + 1).
+        auto * mem_dft = llama_get_memory(ctx_dft);
+        std::vector<llama_pos> dnext(n_seq, 0);
+        for (llama_seq_id seq_id = 0; seq_id < (llama_seq_id) n_seq; ++seq_id) {
+            dnext[seq_id] = llama_memory_seq_pos_max(mem_dft, seq_id) + 1;
+        }
+
         // Flatten token-wise encoder work into shared chunks while preserving each row's position and sequence.
         for (int32_t offset = 0; offset < n_tokens; offset += n_ubatch) {
             const int32_t n_chunk = std::min(n_ubatch, n_tokens - offset);
@@ -1139,7 +1149,7 @@ struct common_speculative_impl_draft_dflash : public common_speculative_impl {
                 GGML_ASSERT(batch_in.n_seq_id[j] == 1);
                 const llama_seq_id seq_id = batch_in.seq_id[j][0];
                 GGML_ASSERT(seq_id >= 0 && seq_id < (llama_seq_id) n_seq);
-                batch_inject.pos[i]       = batch_in.pos[j];
+                batch_inject.pos[i]       = dnext[seq_id]++;
                 batch_inject.n_seq_id[i]  = 1;
                 batch_inject.seq_id[i][0] = seq_id;
                 batch_inject.logits[i]    = false;
@@ -1163,6 +1173,7 @@ struct common_speculative_impl_draft_dflash : public common_speculative_impl {
 
         common_batch_clear(batch);
 
+        auto * mem_dft = llama_get_memory(ctx_dft);
         // build one batch holding every drafting sequence's noise block into a single decode)
         // record where each block starts and its size
         std::vector<int32_t> i_block_beg(n_seq, -1);
@@ -1176,7 +1187,7 @@ struct common_speculative_impl_draft_dflash : public common_speculative_impl {
 
             common_sampler_reset(smpls[seq_id].get());
 
-            const int32_t n = (int32_t) dp.n_past;
+            const int32_t n = llama_memory_seq_pos_max(mem_dft, seq_id) + 1;
 
             const int32_t n_draft = params.n_max;