diff --git a/wrapper/xgboost.py b/wrapper/xgboost.py
index 35c24a1f2..bc52da633 100644
--- a/wrapper/xgboost.py
+++ b/wrapper/xgboost.py
@@ -795,7 +795,7 @@ def train(params, dtrain, num_boost_round=10, evals=(), obj=None, feval=None,
 
                 sys.stderr.write(msg + '\n')
                 if evals_result is not None:
-                    res = re.findall(":([0-9.]+).", msg)
+                    res = re.findall(":-?([0-9.]+).", msg)
                     for key, val in zip(evals_name, res):
                         evals_result[key].append(val)
         return bst
@@ -842,7 +842,7 @@ def train(params, dtrain, num_boost_round=10, evals=(), obj=None, feval=None,
             sys.stderr.write(msg + '\n')
 
             if evals_result is not None:
-                res = re.findall(":([0-9.]+).", msg)
+                res = re.findall(":-([0-9.]+).", msg)
                 for key, val in zip(evals_name, res):
                     evals_result[key].append(val)