diff --git a/src/tetris/rotate.h b/src/tetris/rotate.h
index 67d86b40b..f090f3aa8 100644
--- a/src/tetris/rotate.h
+++ b/src/tetris/rotate.h
@@ -1,12 +1,48 @@
+bool InvalidMove() { // a bit wasteful, but piece are tiny
+  int dy, dx;
+  curpiece_->get_dim(&dy, &dx);
+  while(dy--){
+    int x = dx;
+    while(x--){
+      ncpp::Cell c, b;
+      if(curpiece_->get_at(dy, x, &c) < 0){
+        throw TetrisNotcursesErr("get_at()");
+      }
+      if(c.is_simple()){
+        continue;
+      }
+      curpiece_->release(c);
+      int transy = dy, transx = x; // need game area coordinates via translation
+      curpiece_->translate(*board_, &transy, &transx);
+      if(transy < 0 || transy >= board_->get_dim_y() || transx < 0 || transx >= board_->get_dim_x()){
+        return true;
+      }
+      if(board_->get_at(transy, transx, &b) < 0){
+        throw TetrisNotcursesErr("get_at()");
+      }
+      if(!b.is_simple()){
+        return true;
+      }
+      board_->release(b);
+    }
+  }
+  return false;
+}
+
 void RotateCcw() {
   const std::lock_guard<std::mutex> lock(mtx_);
   int y, x;
   if(!PrepForMove(&y, &x)){
     return;
   }
-  // FIXME need to check game board for validity of rotation in both of these
-  if(!curpiece_->rotate_ccw() || !nc_.render()){
-    throw TetrisNotcursesErr("rotate_ccw() or render()");
+  if(!curpiece_->rotate_ccw()){
+    throw TetrisNotcursesErr("rotate_ccw()");
+  }
+  if(InvalidMove() && !curpiece_->rotate_cw()){
+    throw TetrisNotcursesErr("rotate_cw()");
+  }
+  if(!nc_.render()){
+    throw TetrisNotcursesErr("render()");
   }
 }
 
@@ -16,7 +52,13 @@ void RotateCw() {
   if(!PrepForMove(&y, &x)){
     return;
   }
-  if(!curpiece_->rotate_cw() || !nc_.render()){
-    throw TetrisNotcursesErr("rotate_cw() or render()");
+  if(!curpiece_->rotate_cw()){
+    throw TetrisNotcursesErr("rotate_cw()");
+  }
+  if(InvalidMove() && !curpiece_->rotate_ccw()){
+    throw TetrisNotcursesErr("rotate_ccw()");
+  }
+  if(!nc_.render()){
+    throw TetrisNotcursesErr("render()");
   }
 }