diff --git a/server/upload.go b/server/upload.go
index 3666d7d5..f4dda888 100644
--- a/server/upload.go
+++ b/server/upload.go
@@ -123,19 +123,6 @@ func (b *blobUpload) Run(ctx context.Context, opts *RegistryOptions) {
 	defer blobUploadManager.Delete(b.Digest)
 	ctx, b.CancelFunc = context.WithCancel(ctx)
 
-	p, err := GetBlobsPath(b.Digest)
-	if err != nil {
-		b.err = err
-		return
-	}
-
-	f, err := os.Open(p)
-	if err != nil {
-		b.err = err
-		return
-	}
-	defer f.Close()
-
 	g, inner := errgroup.WithContext(ctx)
 	g.SetLimit(numUploadParts)
 	for i := range b.Parts {
@@ -146,7 +133,6 @@ func (b *blobUpload) Run(ctx context.Context, opts *RegistryOptions) {
 			g.Go(func() error {
 				var err error
 				for try := 0; try < maxRetries; try++ {
-					part.ReadSeeker = io.NewSectionReader(f, part.Offset, part.Size)
 					err = b.uploadChunk(inner, http.MethodPatch, requestURL, part, opts)
 					switch {
 					case errors.Is(err, context.Canceled):
@@ -209,18 +195,27 @@ func (b *blobUpload) Run(ctx context.Context, opts *RegistryOptions) {
 }
 
 func (b *blobUpload) uploadChunk(ctx context.Context, method string, requestURL *url.URL, part *blobUploadPart, opts *RegistryOptions) error {
-	part.Reset()
-
 	headers := make(http.Header)
 	headers.Set("Content-Type", "application/octet-stream")
 	headers.Set("Content-Length", fmt.Sprintf("%d", part.Size))
-	headers.Set("X-Redirect-Uploads", "1")
 
 	if method == http.MethodPatch {
+		headers.Set("X-Redirect-Uploads", "1")
 		headers.Set("Content-Range", fmt.Sprintf("%d-%d", part.Offset, part.Offset+part.Size-1))
 	}
 
-	resp, err := makeRequest(ctx, method, requestURL, headers, io.TeeReader(part.ReadSeeker, io.MultiWriter(part, part.Hash)), opts)
+	p, err := GetBlobsPath(b.Digest)
+	if err != nil {
+		return err
+	}
+
+	f, err := os.Open(p)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	resp, err := makeRequest(ctx, method, requestURL, headers, io.TeeReader(io.NewSectionReader(f, part.Offset, part.Size), part), opts)
 	if err != nil {
 		return err
 	}
@@ -335,7 +330,6 @@ type blobUploadPart struct {
 
 	written int64
 
-	io.ReadSeeker
 	*blobUpload
 }
 
@@ -343,14 +337,20 @@ func (p *blobUploadPart) Write(b []byte) (n int, err error) {
 	n = len(b)
 	p.written += int64(n)
 	p.Completed.Add(int64(n))
+
+	if p.Hash == nil {
+		p.Hash = md5.New()
+	}
+
+	p.Hash.Write(b)
+
 	return n, nil
 }
 
 func (p *blobUploadPart) Reset() {
-	p.Seek(0, io.SeekStart)
 	p.Completed.Add(-int64(p.written))
 	p.written = 0
-	p.Hash = md5.New()
+	p.Hash.Reset()
 }
 
 func uploadBlob(ctx context.Context, mp ModelPath, layer *Layer, opts *RegistryOptions, fn func(api.ProgressResponse)) error {