diff --git a/README.md b/README.md
index 9629580..4a9e6f6 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ composer require sunaoka/laravel-postgres-extension
     - [ ] tstzrange — Range of timestamp with time zone
     - [ ] daterange — Range of date
 
-- [x] UPSERT (ON CONFLICT DO UPDATE)
+- [x] ~~UPSERT (ON CONFLICT DO UPDATE)~~
 
 - [x] RETURNING
     - UPDATE
@@ -80,7 +80,9 @@ echo $some->term->upper()->format('Y-m-d H:i:s'); // upper() or to()
 // => 2020-10-01 23:59:59
 ```
 
-### UPSERT (ON CONFLICT DO UPDATE)
+### ~~UPSERT (ON CONFLICT DO UPDATE)~~
+
+Laravel 8.10.0 adds support for upsert.
 
 ```php
 $result = SomeModel::upsert([
diff --git a/src/Eloquent/Builder.php b/src/Eloquent/Builder.php
index cb9a323..d9c5d81 100644
--- a/src/Eloquent/Builder.php
+++ b/src/Eloquent/Builder.php
@@ -9,23 +9,6 @@
  */
 class Builder extends \Illuminate\Database\Eloquent\Builder
 {
-    /**
-     * @param array $values
-     * @param array $columns
-     *
-     * @return bool|\Illuminate\Database\Eloquent\Collection
-     */
-    public function upsert(array $values, array $columns)
-    {
-        $result = $this->toBase()->upsert($this->addUpdatedAtColumn($values), $columns);
-        if (empty($this->toBase()->returning)) {
-            return $result;
-        }
-
-        /** @var array $result */
-        return !empty($result) ? $this->hydrate($result) : null;
-    }
-
     /**
      * Update records in the database.
      *
diff --git a/src/Query/Builder.php b/src/Query/Builder.php
index 884fb62..c9d1c06 100644
--- a/src/Query/Builder.php
+++ b/src/Query/Builder.php
@@ -71,27 +71,4 @@ public function delete($id = null)
 
         return $this->connection->select($query, $bindings);
     }
-
-    /**
-     * Upsert records in the database.
-     *
-     * @param array $values
-     * @param array $columns
-     *
-     * @return array|bool
-     */
-    public function upsert(array $values, array $columns)
-    {
-        $query = $this->grammar->compileUpsert($this, $values, $columns);
-
-        $bindings = $this->cleanBindings(
-            $this->grammar->prepareBindingsForUpsert($this->bindings, $values)
-        );
-
-        if (empty($this->returning)) {
-            return $this->connection->insert($query, $bindings);
-        }
-
-        return $this->connection->select($query, $bindings);
-    }
 }
diff --git a/src/Query/Grammars/PostgresGrammar.php b/src/Query/Grammars/PostgresGrammar.php
index 3ce806b..45036b1 100644
--- a/src/Query/Grammars/PostgresGrammar.php
+++ b/src/Query/Grammars/PostgresGrammar.php
@@ -80,46 +80,6 @@ public function compileDelete(Builder $query)
         return trim($sql);
     }
 
-    /**
-     * Compile a upsert statement into SQL.
-     *
-     * @param  \Illuminate\Database\Query\Builder  $query
-     * @param  array   $values
-     * @param  array   $columns
-     * @return string
-     */
-    public function compileUpsert(Builder $query, array $values, array $columns)
-    {
-        $values = $this->cleanColumns($values);
-
-        $conflict = collect($columns)->map(function ($value) {
-            return $this->wrap($value);
-        })->implode(', ');
-
-        $update = $this->compileUpdateColumns($query, $values);
-
-        $sql = $this->compileInsert($query, $values);
-        $sql .= " on conflict ({$conflict}) do update set {$update}";
-
-        $sql .= " {$this->compileReturning($query)}";
-
-        return trim($sql);
-    }
-
-    /**
-     * Prepare the bindings for an upsert statement.
-     *
-     * @param  array  $bindings
-     * @param  array  $values
-     * @return array
-     */
-    public function prepareBindingsForUpsert(array $bindings, array $values): array
-    {
-        $bindings = $this->prepareBindingsForUpdate($bindings, $values);
-
-        return array_merge($bindings, $bindings);
-    }
-
     /**
      * Removes the table name from the column name.
      *