@@ -16,6 +16,7 @@ import (

 	"time"

 	"github.com/Sirupsen/logrus"

+	"github.com/docker/distribution/digest"

 	distreference "github.com/docker/distribution/reference"

 	apierrors "github.com/docker/docker/api/errors"

 	apitypes "github.com/docker/docker/api/types"

@@ -1021,6 +1022,9 @@ func (c *Cluster) GetServices(options apitypes.ServiceListOptions) ([]types.Serv

 // TODO(nishanttotla): After the packages converge, the function must

 // convert distreference.Named -> distreference.Canonical, and the logic simplified.

 func (c *Cluster) imageWithDigestString(ctx context.Context, image string, authConfig *apitypes.AuthConfig) (string, error) {

+	if _, err := digest.ParseDigest(image); err == nil {

+		return "", errors.New("image reference is an image ID")

+	}

 	ref, err := distreference.ParseNamed(image)

 	if err != nil {

 		return "", err

@@ -10,6 +10,7 @@ import (

 	"time"

 	"github.com/Sirupsen/logrus"

+	"github.com/docker/distribution/digest"

 	"github.com/docker/docker/api/server/httputils"

 	"github.com/docker/docker/api/types"

 	"github.com/docker/docker/api/types/backend"

@@ -53,6 +54,11 @@ func newContainerAdapter(b executorpkg.Backend, task *api.Task, secrets exec.Sec

 func (c *containerAdapter) pullImage(ctx context.Context) error {

 	spec := c.container.spec()

+	// Skip pulling if the image is referenced by image ID.

+	if _, err := digest.ParseDigest(spec.Image); err == nil {

+		return nil

+	}

+

 	// Skip pulling if the image is referenced by digest and already

 	// exists locally.

 	named, err := reference.ParseNamed(spec.Image)