diff --git a/sqlx-core/src/pool/inner.rs b/sqlx-core/src/pool/inner.rs
index 7e911460..46f37d91 100644
--- a/sqlx-core/src/pool/inner.rs
+++ b/sqlx-core/src/pool/inner.rs
@@ -113,13 +113,13 @@ impl<DB: Database> SharedPool<DB> {
         let mut size = self.size();
 
         while size < self.options.max_connections {
-            let new_size = self.size.compare_and_swap(size, size + 1, Ordering::AcqRel);
-
-            if new_size == size {
-                return Some(DecrementSizeGuard::new(self));
+            match self
+                .size
+                .compare_exchange(size, size + 1, Ordering::AcqRel, Ordering::Acquire)
+            {
+                Ok(_) => return Some(DecrementSizeGuard::new(self)),
+                Err(new_size) => size = new_size,
             }
-
-            size = new_size;
         }
 
         None