diff --git a/README.md b/README.md
index f352a03..c610f4a 100644
--- a/README.md
+++ b/README.md
@@ -215,7 +215,7 @@ vendor/bin/coverage-guard init
 ## Optional dependencies
 - Libraries:
   - `phpunit/php-code-coverage` for loading coverage cov files
-  - `sebastian/diff` for processing diff/patch files
+  - `sebastian/diff` (5.1+) for processing diff/patch files
 - PHP extensions:
   - `ext-libxml` and `ext-simplexml` for loading coverage XML files
   - `ext-dom` for `check` and `merge` commands
diff --git a/composer.json b/composer.json
index 1cb0edc..23bdb5a 100644
--- a/composer.json
+++ b/composer.json
@@ -23,7 +23,7 @@
         "phpstan/phpstan-strict-rules": "2.0.11",
         "phpunit/php-code-coverage": "^10.1",
         "phpunit/phpunit": "~10.5.58",
-        "sebastian/diff": "^4.0 || ^5.0 || ^6.0 || ^7.0",
+        "sebastian/diff": "^5.1.1 || ^6.0 || ^7.0",
         "shipmonk/coding-standard": "^0.2.4",
         "shipmonk/composer-dependency-analyser": "1.8.4",
         "shipmonk/dead-code-detector": "^1.0",
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index d26b1ea..0f94974 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -72,12 +72,6 @@ parameters:
                 - src/Extractor/PhpUnitCoverageExtractor.php
                 - tests/Extractor/PhpUnitCoverageExtractorTest.php
 
-        # support even old sebastian/diff
-        -
-            message: "#Call to function method_exists\\(\\) with SebastianBergmann\\\\Diff.*#"
-            paths:
-                - src/Utils/PatchParser.php
-
         # support even old nikic/php-parser
         -
             message: '#PhpParser\\Node\\Stmt\\Throw_#'
diff --git a/src/Utils/PatchParser.php b/src/Utils/PatchParser.php
index 0d6bae0..e54a1c3 100644
--- a/src/Utils/PatchParser.php
+++ b/src/Utils/PatchParser.php
@@ -12,10 +12,10 @@
 use function file_exists;
 use function file_get_contents;
 use function is_file;
-use function method_exists;
 use function str_ends_with;
 use function str_starts_with;
 use function substr;
+use function version_compare;
 use const DIRECTORY_SEPARATOR;
 
 final class PatchParser
@@ -50,6 +50,12 @@ public function getPatchChangedLines(
             throw new ErrorException('In order to use --patch mode, you need to install sebastian/diff');
         }
 
+        $diffVersion = InstalledVersions::getPrettyVersion('sebastian/diff');
+
+        if ($diffVersion !== null && version_compare($diffVersion, '5.1', '<')) {
+            throw new ErrorException("In order to use --patch mode, you need sebastian/diff 5.1 or newer, {$diffVersion} is installed");
+        }
+
         $gitRoot = $this->resolveGitRoot($config);
         $patchContent = file_get_contents($patchFile);
 
@@ -61,7 +67,7 @@ public function getPatchChangedLines(
         $changes = [];
 
         foreach ($diffs as $diff) {
-            $diffTo = method_exists($diff, 'to') ? $diff->to() : $diff->getTo();
+            $diffTo = $diff->to();
             if ($diffTo === '/dev/null') {
                 continue; // deleted file
             }
@@ -79,14 +85,12 @@ public function getPatchChangedLines(
 
             $changes[$realPath] = [];
 
-            $diffChunks = method_exists($diff, 'chunks') ? $diff->chunks() : $diff->getChunks();
-            foreach ($diffChunks as $chunk) {
-                $lineNumber = method_exists($chunk, 'end') ? $chunk->end() : $chunk->getEnd();
-                $chunkLines = method_exists($chunk, 'lines') ? $chunk->lines() : $chunk->getLines();
+            foreach ($diff->chunks() as $chunk) {
+                $lineNumber = $chunk->end();
 
-                foreach ($chunkLines as $line) {
-                    $lineType = method_exists($line, 'type') ? $line->type() : $line->getType();
-                    $lineContent = method_exists($line, 'content') ? $line->content() : $line->getContent();
+                foreach ($chunk->lines() as $line) {
+                    $lineType = $line->type();
+                    $lineContent = $line->content();
 
                     if ($lineType === Line::ADDED) {
                         if (!isset($actualFileLines[$lineNumber - 1])) {