diff --git a/control/rlocus.py b/control/rlocus.py
index 281fed082..dab21f4ac 100644
--- a/control/rlocus.py
+++ b/control/rlocus.py
@@ -160,7 +160,8 @@ def root_locus_plot(
     from .pzmap import pole_zero_plot
 
     # Legacy parameters
-    gains = config._process_legacy_keyword(kwargs, 'kvect', 'gains', gains)
+    for oldkey in ['kvect', 'k']:
+        gains = config._process_legacy_keyword(kwargs, oldkey, 'gains', gains)
 
     # Set default parameters
     grid = config._get_param('rlocus', 'grid', grid, _rlocus_defaults)
diff --git a/control/tests/rlocus_test.py b/control/tests/rlocus_test.py
index 0b3e868e9..15eb67d97 100644
--- a/control/tests/rlocus_test.py
+++ b/control/tests/rlocus_test.py
@@ -181,10 +181,11 @@ def test_root_locus_plots(sys, grid, xlim, ylim, interactive):
 
 
 # Test deprecated keywords
-def test_root_locus_legacy():
+@pytest.mark.parametrize("keyword", ["kvect", "k"])
+def test_root_locus_legacy(keyword):
     sys = ct.rss(2, 1, 1)
-    with pytest.warns(DeprecationWarning, match="'kvect' is deprecated"):
-        ct.root_locus_plot(sys, kvect=[0, 1, 2])
+    with pytest.warns(DeprecationWarning, match=f"'{keyword}' is deprecated"):
+        ct.root_locus_plot(sys, **{keyword: [0, 1, 2]})
 
 
 # Generate plots used in documentation