diff --git a/src/pineko/cli/convolute.py b/src/pineko/cli/convolute.py
index ba6a2c70..3b1899e7 100644
--- a/src/pineko/cli/convolute.py
+++ b/src/pineko/cli/convolute.py
@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 """CLI entry point to convolution."""
 import click
+import eko
 import pineappl
 import rich
 
@@ -41,6 +42,7 @@ def subcommand(grid_path, op_path, fktable, max_as, max_al, xir, xif, pdf, assum
     PDF is an optional PDF set compatible with the EKO to compare grid and FK table.
     """
     grid = pineappl.grid.Grid.read(grid_path)
+    operators = eko.output.Output.load_tar(op_path)
     rich.print(
         rich.panel.Panel.fit("Computing ...", style="magenta", box=rich.box.SQUARE),
         f"   {grid_path}\n",
@@ -50,7 +52,7 @@ def subcommand(grid_path, op_path, fktable, max_as, max_al, xir, xif, pdf, assum
     )
     _grid, _fk, comp = evolve.evolve_grid(
         grid,
-        op_path,
+        operators,
         fktable,
         max_as,
         max_al,
diff --git a/src/pineko/evolve.py b/src/pineko/evolve.py
index 2dbc5323..56760218 100644
--- a/src/pineko/evolve.py
+++ b/src/pineko/evolve.py
@@ -78,7 +78,7 @@ def write_operator_card(pineappl_grid, default_card, card_path, xif):
 
 def evolve_grid(
     grid,
-    eko_path,
+    operators,
     fktable_path,
     max_as,
     max_al,
@@ -94,7 +94,7 @@ def evolve_grid(
     ----------
     grid : pineappl.grid.Grid
         unconvoluted grid
-    eko_path : str
+    operators : eko.output.Output
         evolution operator
     fktable_path : str
         target path for convoluted grid
@@ -114,7 +114,6 @@ def evolve_grid(
         if given, a comparison table (with / without evolution) will be printed
     """
     _x_grid, _pids, mur2_grid, _muf2_grid = grid.axes()
-    operators = eko.output.Output.load_tar(eko_path)
     check.check_grid_and_eko_compatible(grid, operators, xif)
     # rotate to evolution (if doable and necessary)
     if np.allclose(operators["inputpids"], br.flavor_basis_pids):
diff --git a/src/pineko/theory.py b/src/pineko/theory.py
index 69091257..4a3806af 100644
--- a/src/pineko/theory.py
+++ b/src/pineko/theory.py
@@ -351,6 +351,7 @@ def fk(self, name, grid_path, tcard, pdf):
         xir = tcard["XIR"]
         xif = tcard["XIF"]
         ftr = tcard["fact_to_ren_scale_ratio"]
+        # loading grid
         grid = pineappl.grid.Grid.read(grid_path)
         if not np.isclose(xir, 1.0):
             check.contains_ren(grid)
@@ -376,6 +377,8 @@ def fk(self, name, grid_path, tcard, pdf):
         astrong = sc.StrongCoupling.from_dict(tcard)
         # ocard = self.load_operator_card(name)
         # q2_grid = ocard["Q2grid"]
+
+        # loading ekos
         operators = eko.output.Output.load_tar(eko_filename)
         q2_grid = operators["Q2grid"].keys()
         # PineAPPL wants alpha_s = 4*pi*a_s
@@ -398,7 +401,7 @@ def fk(self, name, grid_path, tcard, pdf):
         )
         _grid, _fk, comparison = evolve.evolve_grid(
             grid,
-            eko_filename,
+            operators,
             fk_filename,
             max_as,
             max_al,