diff --git a/src/devtools.jl b/src/devtools.jl
index 3c42dbf00..882fa1115 100644
--- a/src/devtools.jl
+++ b/src/devtools.jl
@@ -1,4 +1,4 @@
 # Copied from DiffEqDevTools.jl and modified
 # See also: https://devdocs.sciml.ai/dev/alg_dev/test_problems/
-DiffEqDevTools.appxtrue(sol::ProbODESolution, sol2::TestSolution) =
+DiffEqDevTools.appxtrue(sol::ProbODESolution, sol2) =
     DiffEqDevTools.appxtrue(mean(sol), sol2)