diff --git a/cli/cmd/compose/up.go b/cli/cmd/compose/up.go
index e57fff250..fc4f99dd0 100644
--- a/cli/cmd/compose/up.go
+++ b/cli/cmd/compose/up.go
@@ -123,7 +123,7 @@ func runUp(ctx context.Context, opts upOptions, services []string) error {
 		return err
 	}
 
-	err = applyScale(opts.scale, project)
+	err = applyScaleOpt(opts.scale, project)
 	if err != nil {
 		return err
 	}
@@ -142,7 +142,7 @@ func runCreateStart(ctx context.Context, opts upOptions, services []string) erro
 		return err
 	}
 
-	err = applyScale(opts.scale, project)
+	err = applyScaleOpt(opts.scale, project)
 	if err != nil {
 		return err
 	}
@@ -215,8 +215,7 @@ func runCreateStart(ctx context.Context, opts upOptions, services []string) erro
 	return err
 }
 
-func applyScale(opts []string, project *types.Project) error {
-SCALE:
+func applyScaleOpt(opts []string, project *types.Project) error {
 	for _, scale := range opts {
 		split := strings.Split(scale, "=")
 		if len(split) != 2 {
@@ -227,26 +226,33 @@ SCALE:
 		if err != nil {
 			return err
 		}
-		for i, s := range project.Services {
-			if s.Name == name {
-				service, err := project.GetService(name)
-				if err != nil {
-					return err
-				}
-				if service.Deploy == nil {
-					service.Deploy = &types.DeployConfig{}
-				}
-				count := uint64(replicas)
-				service.Deploy.Replicas = &count
-				project.Services[i] = service
-				continue SCALE
-			}
+		err = setServiceScale(project, name, replicas)
+		if err != nil {
+			return err
 		}
-		return fmt.Errorf("unknown service %q", name)
 	}
 	return nil
 }
 
+func setServiceScale(project *types.Project, name string, replicas int) error {
+	for i, s := range project.Services {
+		if s.Name == name {
+			service, err := project.GetService(name)
+			if err != nil {
+				return err
+			}
+			if service.Deploy == nil {
+				service.Deploy = &types.DeployConfig{}
+			}
+			count := uint64(replicas)
+			service.Deploy.Replicas = &count
+			project.Services[i] = service
+			return nil
+		}
+	}
+	return fmt.Errorf("unknown service %q", name)
+}
+
 func setup(ctx context.Context, opts composeOptions, services []string) (*client.Client, *types.Project, error) {
 	c, err := client.NewWithDefaultLocalBackend(ctx)
 	if err != nil {
diff --git a/cli/cmd/compose/up_test.go b/cli/cmd/compose/up_test.go
new file mode 100644
index 000000000..03dac57e0
--- /dev/null
+++ b/cli/cmd/compose/up_test.go
@@ -0,0 +1,42 @@
+/*
+   Copyright 2020 Docker Compose CLI authors
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package compose
+
+import (
+	"testing"
+
+	"github.com/compose-spec/compose-go/types"
+	"gotest.tools/v3/assert"
+)
+
+func TestApplyScaleOpt(t *testing.T) {
+	p := types.Project{
+		Services: []types.ServiceConfig{
+			{
+				Name: "foo",
+			},
+			{
+				Name: "bar",
+			},
+		},
+	}
+	err := applyScaleOpt([]string{"foo=2"}, &p)
+	assert.NilError(t, err)
+	foo, err := p.GetService("foo")
+	assert.NilError(t, err)
+	assert.Check(t, *foo.Deploy.Replicas == 2)
+}