diff --git a/sumpy/tools.py b/sumpy/tools.py
index 3b95349eb886380e1aca8b8ccf6aeb1cd602c23e..c826ef2fe8ea4d3f96e3b8b816dd3500f5efaae8 100644
--- a/sumpy/tools.py
+++ b/sumpy/tools.py
@@ -58,7 +58,9 @@ def mi_factorial(mi):
 def mi_power(vector, mi, evaluate=True):
     result = 1
     for mi_i, vec_i in zip(mi, vector):
-        if evaluate:
+        if mi_i == 1:
+            result *= vec_i
+        elif evaluate:
             result *= vec_i**mi_i
         else:
             result *= sym.unevaluated_pow(vec_i, mi_i)