diff --git a/src/mame/drivers/taito_z.cpp b/src/mame/drivers/taito_z.cpp
index 66cec60baa2..4855ffb9dec 100644
--- a/src/mame/drivers/taito_z.cpp
+++ b/src/mame/drivers/taito_z.cpp
@@ -2601,7 +2601,7 @@ static INPUT_PORTS_START( sci )
 	PORT_BIT( 0x80, IP_ACTIVE_LOW, IPT_UNKNOWN )
 
 	PORT_START("IN1")
-	PORT_BIT( 0x01, IP_ACTIVE_LOW,  IPT_BUTTON4 ) PORT_NAME("Turbo")
+	PORT_BIT( 0x01, IP_ACTIVE_LOW,  IPT_BUTTON3 ) PORT_NAME("Turbo")
 	PORT_BIT( 0x02, IP_ACTIVE_LOW,  IPT_TILT )
 	PORT_BIT( 0x04, IP_ACTIVE_LOW,  IPT_SERVICE2 ) PORT_NAME("Center")
 	PORT_BIT( 0x08, IP_ACTIVE_LOW,  IPT_START1 )