diff --git a/packages/Laravel/src/Rector/Class_/InlineValidationRulesToArrayDefinitionRector.php b/packages/Laravel/src/Rector/Class_/InlineValidationRulesToArrayDefinitionRector.php
new file mode 100644
index 000000000000..cd5260bddab1
--- /dev/null
+++ b/packages/Laravel/src/Rector/Class_/InlineValidationRulesToArrayDefinitionRector.php
@@ -0,0 +1,177 @@
+<?php declare(strict_types=1);
+
+namespace Rector\Laravel\Rector\Class_;
+
+use PhpParser\Node;
+use Rector\Rector\AbstractRector;
+use Rector\RectorDefinition\CodeSample;
+use Rector\RectorDefinition\RectorDefinition;
+
+/**
+ * @see \Rector\Laravel\Tests\Rector\Class_\InlineValidationRulesToArrayDefinitionRector\InlineValidationRulesToArrayDefinitionRectorTest
+ */
+final class InlineValidationRulesToArrayDefinitionRector extends AbstractRector
+{
+    public function getDefinition(): RectorDefinition
+    {
+        return new RectorDefinition('Transforms inline validation rules to array definition', [
+            new CodeSample(
+                <<<'CODE_SAMPLE'
+use Illuminate\Foundation\Http\FormRequest;
+
+class SomeClass extends FormRequest
+{
+    public function rules(): array
+    {
+        return [
+            'someAttribute' => 'required|string|exists:' . SomeModel::class . 'id',
+        ];
+    }
+}
+CODE_SAMPLE
+,
+                <<<'CODE_SAMPLE'
+use Illuminate\Foundation\Http\FormRequest;
+
+class SomeClass extends FormRequest
+{
+    public function rules(): array
+    {
+        return [
+            'someAttribute' => ['required', 'string', \Illuminate\Validation\Rule::exists(SomeModel::class, 'id')],
+        ];
+    }
+}
+CODE_SAMPLE
+
+            )
+        ]);
+    }
+
+    public function getNodeTypes(): array
+    {
+        return [Node\Stmt\Class_::class];
+    }
+
+    /**
+     * @param Node\Stmt\Class_ $node
+     * @return Node|null
+     */
+    public function refactor(Node $node): ?Node
+    {
+        if ($this->isObjectType($node, 'Illuminate\Foundation\Http\FormRequest') === false) {
+            return null;
+        }
+
+        $rules = $node->getMethod('rules');
+        if ($rules === null || $rules->stmts === null) {
+            return null;
+        }
+
+        foreach ($rules->stmts as $statement) {
+            if (!$statement instanceof Node\Stmt\Return_) {
+                continue;
+            }
+
+            $expression = $statement->expr;
+            if (!$expression instanceof Node\Expr\Array_) {
+                continue;
+            }
+
+            foreach ($expression->items as $item) {
+                if (!$item->value instanceof Node\Scalar\String_ && !$item->value instanceof Node\Expr\BinaryOp\Concat) {
+                    continue;
+                }
+
+                $newRules = $this->transformRulesSetToExpressionsArray($item->value);
+                foreach ($newRules as &$newRule) {
+                    if (!($newRule instanceof Node\Expr\BinaryOp\Concat)) {
+                        continue;
+                    }
+
+                    try {
+                        $fullString = $this->transformConcatExpressionToSingleString($newRule);
+                    } catch (\LogicException $exception) {
+                        continue;
+                    }
+
+                    $matchesExist = preg_match('/^exists:(\w+),(\w+)$/', $fullString, $matches);
+                    if ($matchesExist === false || $matchesExist === 0) {
+                        continue;
+                    }
+
+                    $ruleClass = $matches[1];
+                    $ruleAttribute = $matches[2];
+
+                    $newRule = new Node\Expr\StaticCall(
+                        new Node\Name('\Illuminate\Validation\Rule'),
+                        'exists',
+                        [
+                            new Node\Arg(
+                                new Node\Expr\ClassConstFetch(
+                                    new Node\Name($ruleClass),
+                                    'class'
+                                )
+                            ),
+                            new Node\Arg(new Node\Scalar\String_($ruleAttribute)),
+                        ]
+                    );
+                }
+
+                $item->value = $this->createArray($newRules);
+            }
+        }
+
+        return $node;
+    }
+
+    /**
+     * @param Node\Expr $expr
+     * @return Node\Expr[]
+     */
+    private function transformRulesSetToExpressionsArray(Node\Expr $expr): array
+    {
+        if ($expr instanceof Node\Scalar\String_) {
+            return array_map(static function (string $value): Node\Scalar\String_ {
+                return new Node\Scalar\String_($value);
+            }, explode('|', $expr->value));
+        } elseif ($expr instanceof Node\Expr\BinaryOp\Concat) {
+            $left = $this->transformRulesSetToExpressionsArray($expr->left);
+            $expr->left = $left[count($left ) - 1];
+
+            $right = $this->transformRulesSetToExpressionsArray($expr->right);
+            $expr->right = $right [0];
+
+            return array_merge(array_slice($left, 0, -1), [$expr], array_slice($right, 1));
+        } elseif ($expr instanceof Node\Expr\ClassConstFetch
+            || $expr instanceof Node\Expr\MethodCall
+            || $expr instanceof Node\Expr\FuncCall
+        ) {
+            return [$expr];
+        }
+
+        throw new \InvalidArgumentException('Unexpected call ' . get_class($expr));
+    }
+
+    private function transformConcatExpressionToSingleString(Node\Expr\BinaryOp\Concat $expression): string
+    {
+        $output = '';
+
+        foreach ([$expression->left, $expression->right] as $expressionPart) {
+            if ($expressionPart instanceof Node\Scalar\String_) {
+                $output .= $expressionPart->value;
+            } elseif ($expressionPart instanceof Node\Expr\BinaryOp\Concat) {
+                $output .= $this->transformConcatExpressionToSingleString($expressionPart);
+            } elseif ($expressionPart instanceof Node\Expr\ClassConstFetch) {
+                /** @var Node\Name $name */
+                $name = $expressionPart->class->getAttribute('originalName');
+
+                $output .= implode('\\', $name->parts);
+            } else {
+                throw new \LogicException('Unexpected expression type ' . get_class($expressionPart));
+            }
+        }
+
+        return $output;
+    }
+}
diff --git a/packages/Laravel/tests/Rector/Class_/InlineValidationRulesToArrayDefinitionRector/Fixture/fixture.php.inc b/packages/Laravel/tests/Rector/Class_/InlineValidationRulesToArrayDefinitionRector/Fixture/fixture.php.inc
new file mode 100644
index 000000000000..83151b450b08
--- /dev/null
+++ b/packages/Laravel/tests/Rector/Class_/InlineValidationRulesToArrayDefinitionRector/Fixture/fixture.php.inc
@@ -0,0 +1,39 @@
+<?php
+
+namespace Rector\Laravel\Tests\Rector\Class_\InlineValidationRulesToArrayDefinitionRector\Fixture;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class SomeClass extends FormRequest
+{
+    public function rules(): array
+    {
+        return [
+            'someAttribute' => 'required|string|exists:' . SomeModel::class . ',id',
+            'attribute2' => 'required',
+            'attribute3' => 'required|unsupportedRule:' . SomeRule::class,
+        ];
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Laravel\Tests\Rector\Class_\InlineValidationRulesToArrayDefinitionRector\Fixture;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class SomeClass extends FormRequest
+{
+    public function rules(): array
+    {
+        return [
+            'someAttribute' => ['required', 'string', \Illuminate\Validation\Rule::exists(SomeModel::class, 'id')],
+            'attribute2' => ['required'],
+            'attribute3' => ['required', 'unsupportedRule:' . SomeRule::class],
+        ];
+    }
+}
+
+?>
diff --git a/packages/Laravel/tests/Rector/Class_/InlineValidationRulesToArrayDefinitionRector/InlineValidationRulesToArrayDefinitionRectorTest.php b/packages/Laravel/tests/Rector/Class_/InlineValidationRulesToArrayDefinitionRector/InlineValidationRulesToArrayDefinitionRectorTest.php
new file mode 100644
index 000000000000..4b53d847c608
--- /dev/null
+++ b/packages/Laravel/tests/Rector/Class_/InlineValidationRulesToArrayDefinitionRector/InlineValidationRulesToArrayDefinitionRectorTest.php
@@ -0,0 +1,19 @@
+<?php declare(strict_types=1);
+
+namespace Rector\Laravel\Tests\Rector\Class_\InlineValidationRulesToArrayDefinitionRector;
+
+use Rector\Laravel\Rector\Class_\InlineValidationRulesToArrayDefinitionRector;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class InlineValidationRulesToArrayDefinitionRectorTest extends AbstractRectorTestCase
+{
+    public function test(): void
+    {
+        $this->doTestFile(__DIR__ . '/Fixture/fixture.php.inc');
+    }
+
+    protected function getRectorClass(): string
+    {
+        return InlineValidationRulesToArrayDefinitionRector::class;
+    }
+}
diff --git a/src/PhpParser/Node/NodeFactory.php b/src/PhpParser/Node/NodeFactory.php
index 6b919fdc3ae6..385013cc105a 100644
--- a/src/PhpParser/Node/NodeFactory.php
+++ b/src/PhpParser/Node/NodeFactory.php
@@ -219,7 +219,13 @@ private function createArrayItem($item, $key = null): ArrayItem
     {
         $arrayItem = null;
 
-        if ($item instanceof Variable) {
+        if ($item instanceof Variable
+            || $item instanceof String_
+            || $item instanceof MethodCall
+            || $item instanceof StaticCall
+            || $item instanceof Expr\FuncCall
+            || $item instanceof Expr\BinaryOp\Concat
+        ) {
             $arrayItem = new ArrayItem($item);
         } elseif ($item instanceof Identifier) {
             $string = new String_($item->toString());
diff --git a/stubs/Illuminate/Foundation/Http/FormRequest.php b/stubs/Illuminate/Foundation/Http/FormRequest.php
new file mode 100644
index 000000000000..ac5122f774a9
--- /dev/null
+++ b/stubs/Illuminate/Foundation/Http/FormRequest.php
@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Illuminate\Foundation\Http;
+
+if (class_exists('Illuminate\Foundation\Http\FormRequest')) {
+    return;
+}
+
+class FormRequest
+{
+}