diff --git a/file/file_prefetch_buffer.cc b/file/file_prefetch_buffer.cc
index 77539abd2..cef339196 100644
--- a/file/file_prefetch_buffer.cc
+++ b/file/file_prefetch_buffer.cc
@@ -66,6 +66,17 @@ void FilePrefetchBuffer::CalculateOffsetAndLen(size_t alignment,
     // chunk_len is greater than 0.
     bufs_[index].buffer_.RefitTail(static_cast<size_t>(chunk_offset_in_buffer),
                                    static_cast<size_t>(chunk_len));
+  } else if (chunk_len > 0) {
+    // For async prefetching, it doesn't call RefitTail with chunk_len > 0.
+    // Allocate new buffer if needed because aligned buffer calculate remaining
+    // buffer as capacity_ - cursize_ which might not be the case in this as we
+    // are not refitting.
+    // TODO akanksha: Update the condition when asynchronous prefetching is
+    // stable.
+    bufs_[index].buffer_.Alignment(alignment);
+    bufs_[index].buffer_.AllocateNewBuffer(
+        static_cast<size_t>(roundup_len), copy_data_to_new_buffer,
+        chunk_offset_in_buffer, static_cast<size_t>(chunk_len));
   }
 }
 
@@ -236,34 +247,47 @@ Status FilePrefetchBuffer::PrefetchAsync(const IOOptions& opts,
   // Index of second buffer.
   uint32_t second = curr_ ^ 1;
 
+  // First clear the buffers if it contains outdated data. Outdated data can be
+  // because previous sequential reads were read from the cache instead of these
+  // buffer.
+  {
+    if (bufs_[curr_].buffer_.CurrentSize() > 0 &&
+        offset >= bufs_[curr_].offset_ + bufs_[curr_].buffer_.CurrentSize()) {
+      bufs_[curr_].buffer_.Clear();
+    }
+    if (bufs_[second].buffer_.CurrentSize() > 0 &&
+        offset >= bufs_[second].offset_ + bufs_[second].buffer_.CurrentSize()) {
+      bufs_[second].buffer_.Clear();
+    }
+  }
+
   // If data is in second buffer, make it curr_. Second buffer can be either
   // partial filled or full.
   if (bufs_[second].buffer_.CurrentSize() > 0 &&
       offset >= bufs_[second].offset_ &&
-      offset <= bufs_[second].offset_ + bufs_[second].buffer_.CurrentSize()) {
+      offset < bufs_[second].offset_ + bufs_[second].buffer_.CurrentSize()) {
     // Clear the curr_ as buffers have been swapped and curr_ contains the
-    // outdated data.
+    // outdated data and switch the buffers.
     bufs_[curr_].buffer_.Clear();
-    // Switch the buffers.
     curr_ = curr_ ^ 1;
     second = curr_ ^ 1;
   }
-
-  // If second buffer contains outdated data, clear it for async prefetching.
-  // Outdated can be because previous sequential reads were read from the cache
-  // instead of this buffer.
-  if (bufs_[second].buffer_.CurrentSize() > 0 &&
-      offset >= bufs_[second].offset_ + bufs_[second].buffer_.CurrentSize()) {
-    bufs_[second].buffer_.Clear();
+  // After swap check if all the requested bytes are in curr_, it will go for
+  // async prefetching only.
+  if (bufs_[curr_].buffer_.CurrentSize() > 0 &&
+      offset + length <=
+          bufs_[curr_].offset_ + bufs_[curr_].buffer_.CurrentSize()) {
+    offset += length;
+    length = 0;
+    prefetch_size -= length;
   }
-
   // Data is overlapping i.e. some of the data is in curr_ buffer and remaining
   // in second buffer.
   if (bufs_[curr_].buffer_.CurrentSize() > 0 &&
       bufs_[second].buffer_.CurrentSize() > 0 &&
       offset >= bufs_[curr_].offset_ &&
       offset < bufs_[curr_].offset_ + bufs_[curr_].buffer_.CurrentSize() &&
-      offset + prefetch_size > bufs_[second].offset_) {
+      offset + length > bufs_[second].offset_) {
     // Allocate new buffer to third buffer;
     bufs_[2].buffer_.Clear();
     bufs_[2].buffer_.Alignment(alignment);
@@ -273,12 +297,10 @@ Status FilePrefetchBuffer::PrefetchAsync(const IOOptions& opts,
 
     // Move data from curr_ buffer to third.
     CopyDataToBuffer(curr_, offset, length);
-
     if (length == 0) {
       // Requested data has been copied and curr_ still has unconsumed data.
       return s;
     }
-
     CopyDataToBuffer(second, offset, length);
     // Length == 0: All the requested data has been copied to third buffer. It
     // should go for only async prefetching.
@@ -306,6 +328,7 @@ Status FilePrefetchBuffer::PrefetchAsync(const IOOptions& opts,
   if (length > 0) {
     CalculateOffsetAndLen(alignment, offset, roundup_len1, curr_,
                           false /*refit_tail*/, chunk_len1);
+    assert(roundup_len1 >= chunk_len1);
     read_len1 = static_cast<size_t>(roundup_len1 - chunk_len1);
   }
   {
@@ -316,7 +339,7 @@ Status FilePrefetchBuffer::PrefetchAsync(const IOOptions& opts,
         Roundup(rounddown_start2 + readahead_size, alignment);
 
     // For length == 0, do the asynchronous prefetching in second instead of
-    // synchronous prefetching of remaining prefetch_size.
+    // synchronous prefetching in curr_.
     if (length == 0) {
       rounddown_start2 =
           bufs_[curr_].offset_ + bufs_[curr_].buffer_.CurrentSize();
@@ -330,8 +353,8 @@ Status FilePrefetchBuffer::PrefetchAsync(const IOOptions& opts,
 
     // Update the buffer offset.
     bufs_[second].offset_ = rounddown_start2;
+    assert(roundup_len2 >= chunk_len2);
     uint64_t read_len2 = static_cast<size_t>(roundup_len2 - chunk_len2);
-
     ReadAsync(opts, reader, rate_limiter_priority, read_len2, chunk_len2,
               rounddown_start2, second)
         .PermitUncheckedError();
@@ -344,7 +367,6 @@ Status FilePrefetchBuffer::PrefetchAsync(const IOOptions& opts,
       return s;
     }
   }
-
   // Copy remaining requested bytes to third_buffer.
   if (copy_to_third_buffer && length > 0) {
     CopyDataToBuffer(curr_, offset, length);