diff --git a/android/assets/jsons/Units.json b/android/assets/jsons/Units.json
index 481b8bbbca..ff09910e4c 100644
--- a/android/assets/jsons/Units.json
+++ b/android/assets/jsons/Units.json
@@ -130,7 +130,7 @@
 		name:"Ballista",
 		unitType:"Siege",
 		uniqueTo:"Rome",
-		replaces:"Horseman",
+		replaces:"Catapult",
 		movement:2,
 		strength:8,
 		rangedStrength:10,
diff --git a/core/src/com/unciv/ui/pickerscreens/ImprovementPickerScreen.kt b/core/src/com/unciv/ui/pickerscreens/ImprovementPickerScreen.kt
index c201e2b991..180cf51021 100644
--- a/core/src/com/unciv/ui/pickerscreens/ImprovementPickerScreen.kt
+++ b/core/src/com/unciv/ui/pickerscreens/ImprovementPickerScreen.kt
@@ -29,7 +29,10 @@ class ImprovementPickerScreen(tileInfo: TileInfo) : PickerScreen() {
         val regularImprovements = VerticalGroup()
         regularImprovements.space(10f)
         for (improvement in GameBasics.TileImprovements.values) {
-            if (!tileInfo.canBuildImprovement(improvement, civInfo) || improvement.name == tileInfo.improvement) continue
+            if (!tileInfo.canBuildImprovement(improvement, civInfo)) continue
+            if(improvement.name == tileInfo.improvement) continue
+            if(improvement.name==tileInfo.improvementInProgress) continue
+            
             val improvementButton = Button(skin)
 
             if(improvement.name.startsWith("Remove"))