diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/reactor/ScopePassingSpanSubscriber.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/reactor/ScopePassingSpanSubscriber.java
index ac56b67b0..9561b6545 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/reactor/ScopePassingSpanSubscriber.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/reactor/ScopePassingSpanSubscriber.java
@@ -46,8 +46,8 @@ final class ScopePassingSpanSubscriber<T> extends AtomicBoolean implements SpanS
 		Span root = ctx != null ?
 				ctx.getOrDefault(Span.class, this.tracer.currentSpan()) : null;
 		this.span = root;
-		this.context = root != null ?
-				ctx.put(Span.class, root): Context.empty();
+		this.context = ctx != null && root != null ? ctx.put(Span.class, root) :
+				ctx != null ? ctx : Context.empty();
 	}
 
 	@Override public void onSubscribe(Subscription subscription) {
diff --git a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/reactor/ScopePassingSpanSubscriberTests.java b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/reactor/ScopePassingSpanSubscriberTests.java
new file mode 100644
index 000000000..eef935906
--- /dev/null
+++ b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/reactor/ScopePassingSpanSubscriberTests.java
@@ -0,0 +1,64 @@
+/*
+ * Copyright 2013-2018 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.cloud.sleuth.instrument.reactor;
+
+import brave.Span;
+import brave.Tracer;
+import brave.Tracing;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.junit.MockitoJUnitRunner;
+import reactor.util.context.Context;
+
+import static org.assertj.core.api.BDDAssertions.then;
+
+/**
+ * @author Marcin Grzejszczak
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class ScopePassingSpanSubscriberTests {
+
+	Tracing tracing = Tracing.newBuilder().build();
+
+	@Test
+	public void should_propagate_current_context() {
+		ScopePassingSpanSubscriber subscriber = new ScopePassingSpanSubscriber(
+				null, Context.of("foo", "bar"), this.tracing);
+
+		then((String) subscriber.currentContext().get("foo")).isEqualTo("bar");
+	}
+
+	@Test
+	public void should_set_empty_context_when_context_is_null() {
+		ScopePassingSpanSubscriber subscriber = new ScopePassingSpanSubscriber(
+				null, null, this.tracing);
+
+		then(subscriber.currentContext().isEmpty()).isTrue();
+	}
+
+	@Test
+	public void should_put_current_span_to_context() {
+		Span span = this.tracing.tracer().nextSpan();
+		try (Tracer.SpanInScope ws = this.tracing.tracer().withSpanInScope(span.start())) {
+			ScopePassingSpanSubscriber subscriber = new ScopePassingSpanSubscriber(
+					null, Context.empty(), this.tracing);
+
+			then(subscriber.currentContext().get(Span.class)).isEqualTo(span);
+		}
+
+	}
+}
\ No newline at end of file