diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/FileConnections.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/FileConnections.java
index b1717cbd0978c908ead547dead845cd767f7c277..548dc1d937d8a2e00b58475ca80bae1033ae074a 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/FileConnections.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/FileConnections.java
@@ -229,9 +229,14 @@ public class FileConnections {
          */
         final RCompression.Type cTypeActual;
         if (!raw && (openMode == AbstractOpenMode.Read || openMode == AbstractOpenMode.ReadBinary)) {
-            cTypeActual = RCompression.getCompressionType(base.path);
-            if (cTypeActual != cType) {
+            RCompression.Type cTypeFound = RCompression.getCompressionType(base.path);
+            // For binary reading force file's compression type if compression exists
+            // and it conflicts with requested compression type.
+            if (cTypeFound != cType && (openMode != AbstractOpenMode.ReadBinary || cType != RCompression.Type.NONE)) {
+                cTypeActual = cTypeFound;
                 base.updateConnectionClass(mapConnectionClass(cTypeActual));
+            } else {
+                cTypeActual = cType;
             }
         } else {
             cTypeActual = cType;
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
index 4f9e0dee9a33b5c9048a5e41b9967d1df70c6702..7c7844eec54af3ed8f929db16c05ba7670fdbe5a 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
@@ -85281,6 +85281,10 @@ Error in cat(x, file = file, sep = c(rep.int(sep, ncolumns - 1), "\n"),  :
 [126] 00 00 02 00 04 00 09 00 00 00 01 61 00 04 00 09 00 00 00 01 62 00 00 00 fe
 [151] 00 00 00 fe
 
+##com.oracle.truffle.r.test.library.base.TestConnections.testRawWriteBinary#
+#f <- tempfile(); unlink(f); x <- 1:10; save(x, file=f); con <- file(f, 'rb'); dput(class(con))
+c("file", "connection")
+
 ##com.oracle.truffle.r.test.library.base.TestConnections.testRawWriteBinary#Ignored.ImplementationError#
 #{ s <- "äöüß"; rc <- rawConnection(raw(0), "wb"); write(charToRaw(s), rc); res <- rawConnectionValue(rc); close(rc); res }
  [1] 63 33 20 61 34 20 63 33 20 62 36 20 63 33 0a 62 63 20 63 33 20 39 66 0a
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestConnections.java b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestConnections.java
index 9129f3984ce7819fe8cab6613e71cbff68706f4c..55b38976abe9eac9efc4ba341b4e395149f4331f 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestConnections.java
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestConnections.java
@@ -247,6 +247,7 @@ public class TestConnections extends TestRBase {
         assertEval("conn <- rawConnection(raw(0), \"wb\"); value <- list(a=c(1,2,3), b='foo'); save(value, file=conn); rawConnectionValue(conn)");
         // ignored because save refuses to write to a rawConnection that is not configured to binary
         assertEval(Ignored.ImplementationError, "conn <- rawConnection(raw(0), \"w\"); value <- c(1,2,3); save(value, file=conn); rawConnectionValue(conn)");
+        assertEval("f <- tempfile(); unlink(f); x <- 1:10; save(x, file=f); con <- file(f, 'rb'); dput(class(con))");
     }
 
     @Test