diff --git a/src/rsz/src/Resizer.tcl b/src/rsz/src/Resizer.tcl
index 7aae430f85..5ae139fbc8 100644
--- a/src/rsz/src/Resizer.tcl
+++ b/src/rsz/src/Resizer.tcl
@@ -760,14 +760,15 @@ proc replace_arith_modules { args } {
   } else {
     set target "setup"
   }
-  if { [info exists keys(-slack_margin)] } {
-    set slack_margin [rsz::parse_time_margin_arg "-slack_margin" keys]
+  if { [info exists keys(-slack_threshold)] } {
+    set slack_threshold [rsz::parse_time_margin_arg "-slack_threshold" keys]
   } else {
-    set slack_margin 0.0
+    set slack_threshold 0.0
   }
 
-  puts "replace_arith_module -path_count $path_count -target $target -slack_margin $slack_margin"
-  rsz::swap_arith_modules_cmd $path_count $target $slack_margin
+  puts [format "replace_arith_modules -path_count %s -target %s -slack_threshold %s" \
+    $path_count $target $slack_threshold]
+  rsz::swap_arith_modules_cmd $path_count $target $slack_threshold
 }
 
 sta::define_cmd_args "report_buffers" { [-filtered] }
diff --git a/src/rsz/test/replace_arith_modules1.ok b/src/rsz/test/replace_arith_modules1.ok
index e46cc619bd..415fd243d4 100644
--- a/src/rsz/test/replace_arith_modules1.ok
+++ b/src/rsz/test/replace_arith_modules1.ok
@@ -14,7 +14,7 @@
 number instances in verilog is 39260
 wns max -85.02
 tns max -174582.05
-replace_arith_module -path_count 100 -target setup -slack_margin 0.0
+replace_arith_modules -path_count 100 -target setup -slack_threshold 0.0
 [INFO RSZ-0151] Starting arithmetic module replacement to optimize 'setup' target
 [INFO RSZ-0152] Analyzing 100 critical paths with slack < 0.00
 [INFO RSZ-0153] Identified 3788 violating endpoints
diff --git a/src/rsz/test/replace_arith_modules2.ok b/src/rsz/test/replace_arith_modules2.ok
index 06e54c7d93..6540605bfd 100644
--- a/src/rsz/test/replace_arith_modules2.ok
+++ b/src/rsz/test/replace_arith_modules2.ok
@@ -14,7 +14,7 @@
 number instances in verilog is 39324
 wns max -85.02
 tns max -174555.69
-replace_arith_module -path_count 100 -target setup -slack_margin 0.0
+replace_arith_modules -path_count 100 -target setup -slack_threshold 0.0
 [INFO RSZ-0151] Starting arithmetic module replacement to optimize 'setup' target
 [INFO RSZ-0152] Analyzing 100 critical paths with slack < 0.00
 [INFO RSZ-0153] Identified 3787 violating endpoints
diff --git a/src/rsz/test/replace_arith_modules3.ok b/src/rsz/test/replace_arith_modules3.ok
index 2dcd0339ff..6d6d94bda6 100644
--- a/src/rsz/test/replace_arith_modules3.ok
+++ b/src/rsz/test/replace_arith_modules3.ok
@@ -81,7 +81,7 @@ Using 2 tracks default min distance between IO pins.
 number instances in verilog is 39260
 wns max -85.02
 tns max -174582.05
-replace_arith_module -path_count 100 -target setup -slack_margin 0.0
+replace_arith_modules -path_count 100 -target setup -slack_threshold 0.0
 [INFO RSZ-0151] Starting arithmetic module replacement to optimize 'setup' target
 [INFO RSZ-0152] Analyzing 100 critical paths with slack < 0.00
 [INFO RSZ-0153] Identified 3788 violating endpoints