diff --git a/yo.go b/yo.go
index 2f0ba0f..44c155c 100644
--- a/yo.go
+++ b/yo.go
@@ -24,9 +24,9 @@ type Yoable[Y any] interface {
 type Opt[T Yoable[T]] func(*Model[T])
 
 // WithSpannerClientOption returns an Opt that sets the spanner client.
-func WithSpannerClientOption[T Yoable[T]](c spanner.Client) Opt[T] {
+func WithSpannerClientOption[T Yoable[T]](c *spanner.Client) Opt[T] {
 	return func(m *Model[T]) {
-		m.Client = c
+		m.Client = *c
 	}
 }
 
diff --git a/yo_test.go b/yo_test.go
index af5015e..0016f24 100644
--- a/yo_test.go
+++ b/yo_test.go
@@ -179,7 +179,7 @@ func TestModel_Apply(t *testing.T) {
 			defer cleanup()
 
 			m := NewModel(tt.fields.model,
-				WithSpannerClientOption[*user.User](*spannerClient),
+				WithSpannerClientOption[*user.User](spannerClient),
 			)
 
 			before, after := tt.mutType.Hooks()