diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/reftable/ReftableTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/reftable/ReftableTest.java
index a142166..db9a4d0a 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/reftable/ReftableTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/reftable/ReftableTest.java
@@ -472,6 +472,51 @@ public void withReflog() throws IOException {
 	}
 
 	@Test
+	public void reflogSeek() throws IOException {
+		PersonIdent who = new PersonIdent("Log", "Ger", 1500079709, -8 * 60);
+		String msg = "test";
+		String msgNext = "test next";
+
+		ByteArrayOutputStream buffer = new ByteArrayOutputStream();
+		ReftableWriter writer = new ReftableWriter()
+				.setMinUpdateIndex(1)
+				.setMaxUpdateIndex(1)
+				.begin(buffer);
+
+		writer.writeLog(MASTER, 1, who, ObjectId.zeroId(), id(1), msg);
+		writer.writeLog(NEXT, 1, who, ObjectId.zeroId(), id(2), msgNext);
+
+		writer.finish();
+		byte[] table = buffer.toByteArray();
+
+		ReftableReader t = read(table);
+		try (LogCursor c = t.seekLog(MASTER, Long.MAX_VALUE)) {
+			assertTrue(c.next());
+			assertEquals(c.getReflogEntry().getComment(), msg);
+		}
+		try (LogCursor c = t.seekLog(MASTER, 0)) {
+			assertFalse(c.next());
+		}
+		try (LogCursor c = t.seekLog(MASTER, 1)) {
+			assertTrue(c.next());
+			assertEquals(c.getUpdateIndex(), 1);
+			assertEquals(c.getReflogEntry().getComment(), msg);
+		}
+		try (LogCursor c = t.seekLog(NEXT, Long.MAX_VALUE)) {
+			assertTrue(c.next());
+			assertEquals(c.getReflogEntry().getComment(), msgNext);
+		}
+		try (LogCursor c = t.seekLog(NEXT, 0)) {
+			assertFalse(c.next());
+		}
+		try (LogCursor c = t.seekLog(NEXT, 1)) {
+			assertTrue(c.next());
+			assertEquals(c.getUpdateIndex(), 1);
+			assertEquals(c.getReflogEntry().getComment(), msgNext);
+		}
+	}
+
+	@Test
 	public void onlyReflog() throws IOException {
 		PersonIdent who = new PersonIdent("Log", "Ger", 1500079709, -8 * 60);
 		String msg = "test";
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableReader.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableReader.java
index bf3a9ae..226e675 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableReader.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableReader.java
@@ -255,6 +255,32 @@ private BlockReader seek(byte blockType, byte[] key, BlockReader idx,
 			block.seekKey(key);
 			return block;
 		}
+		if (blockType == LOG_BLOCK_TYPE) {
+			// No index. Log blocks are irregularly sized, so we can't do binary search
+			// between blocks. Scan over blocks instead.
+			BlockReader block = readBlock(startPos, endPos);
+
+			for (;;) {
+				if (block == null || block.type() != LOG_BLOCK_TYPE) {
+					return null;
+				}
+
+				int result = block.seekKey(key);
+				if (result <= 0) {
+					// == 0 : we found the key.
+					// < 0 : the key is before this block. Either the ref name is there
+					// but only at a newer updateIndex, or it is absent. We leave it to
+					// logcursor to distinguish between both cases.
+					return block;
+				}
+
+				long pos = block.endPosition();
+				if (pos >= endPos) {
+					return null;
+				}
+				block = readBlock(pos, endPos);
+			}
+		}
 		return binarySearch(blockType, key, startPos, endPos);
 	}