diff --git a/ChangeLog.md b/ChangeLog.md
index 89c5cfe..7f8eb3c 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -23,6 +23,10 @@
 3. The ARM 64-bit (ARMv8) NEON SIMD extensions can now be built using MinGW
 toolchains targetting ARM64 (AArch64) Windows binaries.
 
+4. Fixed unexpected visual artifacts that occurred when using
+`jpeg_crop_scanline()` and interblock smoothing while decompressing only the
+DC scan of a progressive JPEG image.
+
 
 2.0.5
 =====
diff --git a/jdcoefct.c b/jdcoefct.c
index 723a9ac..2ba6aa1 100644
--- a/jdcoefct.c
+++ b/jdcoefct.c
@@ -6,7 +6,7 @@
  * libjpeg-turbo Modifications:
  * Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
  * Copyright (C) 2010, 2015-2016, D. R. Commander.
- * Copyright (C) 2015, Google, Inc.
+ * Copyright (C) 2015, 2020, Google, Inc.
  * For conditions of distribution and use, see the accompanying README.ijg
  * file.
  *
@@ -495,11 +495,13 @@
       if (first_row && block_row == 0)
         prev_block_row = buffer_ptr;
       else
-        prev_block_row = buffer[block_row - 1];
+        prev_block_row = buffer[block_row - 1] +
+                         cinfo->master->first_MCU_col[ci];
       if (last_row && block_row == block_rows - 1)
         next_block_row = buffer_ptr;
       else
-        next_block_row = buffer[block_row + 1];
+        next_block_row = buffer[block_row + 1] +
+                         cinfo->master->first_MCU_col[ci];
       /* We fetch the surrounding DC values using a sliding-register approach.
        * Initialize all nine here so as to do the right thing on narrow pics.
        */