diff --git a/sim/battle-stream.ts b/sim/battle-stream.ts
index 67a5483c88..7a7e0e058a 100644
--- a/sim/battle-stream.ts
+++ b/sim/battle-stream.ts
@@ -265,22 +265,22 @@ export function getPlayerStreams(stream: BattleStream) {
 		}),
 		p1: new Streams.ObjectReadWriteStream({
 			write(data: string) {
-				void stream.write(data.replace(/(^|\n)/g, `$1>p1 `));
+				void stream.write(data.replace(/([^\n]+)/g, '>p1 $1'));
 			},
 		}),
 		p2: new Streams.ObjectReadWriteStream({
 			write(data: string) {
-				void stream.write(data.replace(/(^|\n)/g, `$1>p2 `));
+				void stream.write(data.replace(/([^\n]+)/g, '>p2 $1'));
 			},
 		}),
 		p3: new Streams.ObjectReadWriteStream({
 			write(data: string) {
-				void stream.write(data.replace(/(^|\n)/g, `$1>p3 `));
+				void stream.write(data.replace(/([^\n]+)/g, '>p3 $1'));
 			},
 		}),
 		p4: new Streams.ObjectReadWriteStream({
 			write(data: string) {
-				void stream.write(data.replace(/(^|\n)/g, `$1>p4 `));
+				void stream.write(data.replace(/([^\n]+)/g, '>p4 $1'));
 			},
 		}),
 	};