diff --git a/release-tools/src/main/java/org/springframework/data/release/issues/jira/Jira.java b/release-tools/src/main/java/org/springframework/data/release/issues/jira/Jira.java
index f73b7ad..86b043b 100644
--- a/release-tools/src/main/java/org/springframework/data/release/issues/jira/Jira.java
+++ b/release-tools/src/main/java/org/springframework/data/release/issues/jira/Jira.java
@@ -309,12 +309,12 @@ class Jira implements JiraConnector {
 			return;
 		}
 
-		JiraIssue jiraIssue = JiraIssue.create().assignTo(jiraProperties.getCredentials());
+		JiraIssueUpdate editMeta = JiraIssueUpdate.create().assignTo(jiraProperties.getUsername());
 
 		logger.log("Ticket", "Self-assignment of %s", ticket);
 
 		try {
-			operations.exchange(ISSUE_TEMPLATE, HttpMethod.POST, new HttpEntity<Object>(jiraIssue, httpHeaders), String.class,
+			operations.exchange(ISSUE_TEMPLATE, HttpMethod.PUT, new HttpEntity<Object>(editMeta, httpHeaders), String.class,
 					parameters).getBody();
 		} catch (HttpClientErrorException e) {
 			logger.warn("Ticket", "Self-assignment of %s failed with status ", ticket, e.getStatusCode());
diff --git a/release-tools/src/main/java/org/springframework/data/release/issues/jira/JiraIssue.java b/release-tools/src/main/java/org/springframework/data/release/issues/jira/JiraIssue.java
index 591e8c9..0814a66 100644
--- a/release-tools/src/main/java/org/springframework/data/release/issues/jira/JiraIssue.java
+++ b/release-tools/src/main/java/org/springframework/data/release/issues/jira/JiraIssue.java
@@ -86,29 +86,6 @@ class JiraIssue {
 				&& fields.hasSummary(Tracker.releaseTicketSummary(moduleIteration));
 	}
 
-	/**
-	 * Assign to the user specified in {@link Credentials}.
-	 *
-	 * @param credentials must not be {@literal null}.
-	 * @return
-	 */
-	public JiraIssue assignTo(Credentials credentials) {
-		return assignTo(credentials.getUsername());
-	}
-
-	/**
-	 * Assign the ticket to {@code username}.
-	 *
-	 * @param username must not be empty and not {@literal null}.
-	 * @return
-	 */
-	public JiraIssue assignTo(String username) {
-
-		Assert.hasText(username, "Username must not be empty!");
-		getFields().setAssignee(JiraUser.from(username));
-		return this;
-	}
-
 	/**
 	 * Set the project to {@code projectKey}.
 	 *
diff --git a/release-tools/src/main/java/org/springframework/data/release/issues/jira/JiraIssueUpdate.java b/release-tools/src/main/java/org/springframework/data/release/issues/jira/JiraIssueUpdate.java
new file mode 100644
index 0000000..9c59a3e
--- /dev/null
+++ b/release-tools/src/main/java/org/springframework/data/release/issues/jira/JiraIssueUpdate.java
@@ -0,0 +1,78 @@
+package org.springframework.data.release.issues.jira;
+
+import lombok.NonNull;
+import lombok.Value;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.springframework.util.Assert;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+
+/**
+ * Value object to represent a Jira issue update via {@code PUT} with {@code update} fields.
+ *
+ * @author Mark Paluch
+ */
+@Value
+class JiraIssueUpdate {
+
+	private final Map<String, Object> update;
+
+	private JiraIssueUpdate(Map<String, Object> update) {
+		this.update = update;
+	}
+
+	/**
+	 * Create an empty {@link JiraIssueUpdate}.
+	 *
+	 * @return
+	 */
+	public static JiraIssueUpdate create() {
+		return new JiraIssueUpdate(Collections.emptyMap());
+	}
+
+	/**
+	 * Assign the issue to {@code userId}.
+	 *
+	 * @param userId must not be {@literal null} or empty.
+	 * @return
+	 */
+	public JiraIssueUpdate assignTo(String userId) {
+
+		Assert.hasText(userId, "UserId must not be null or empty!");
+
+		Map<String, Object> update = new LinkedHashMap<>(this.update);
+		update.put("assignee", new AssignTo(userId));
+
+		return new JiraIssueUpdate(update);
+	}
+
+	/**
+	 * Serializes as [ {"set": "value"} ]
+	 */
+	@Value
+	@JsonSerialize(using = SetSerializer.class)
+	static class AssignTo {
+		final @NonNull String value;
+	}
+
+	static class SetSerializer extends JsonSerializer<AssignTo> {
+
+		@Override
+		public void serialize(AssignTo value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
+
+			gen.writeStartArray();
+
+			gen.writeObject(Collections.singletonMap("set", Collections.singletonMap("name", value.getValue())));
+
+			gen.writeEndArray();
+		}
+	}
+}
diff --git a/release-tools/src/test/java/org/springframework/data/release/issues/jira/JiraConnectorIntegrationTests.java b/release-tools/src/test/java/org/springframework/data/release/issues/jira/JiraConnectorIntegrationTests.java
index d5f904a..9cfe0ef 100644
--- a/release-tools/src/test/java/org/springframework/data/release/issues/jira/JiraConnectorIntegrationTests.java
+++ b/release-tools/src/test/java/org/springframework/data/release/issues/jira/JiraConnectorIntegrationTests.java
@@ -54,12 +54,12 @@ import com.github.tomakehurst.wiremock.junit.WireMockRule;
  */
 public class JiraConnectorIntegrationTests extends AbstractIntegrationTests {
 
-	public static final String CREATE_ISSUE_URI = "/rest/api/2/issue";
-	public static final String CREATE_VERSION_URI = "/rest/api/2/version";
-	public static final String SEARCH_URI = "/rest/api/2/search";
-	public static final String PROJECT_VERSION_URI = "/rest/api/2/project/%s/version";
-	public static final String PROJECT_COMPONENTS_URI = "/rest/api/2/project/%s/components";
-	public static final ModuleIteration REST_HOPPER_RC1 = ReleaseTrains.HOPPER.getModuleIteration(Iteration.RC1, "REST");
+	static final String CREATE_ISSUE_URI = "/rest/api/2/issue";
+	static final String CREATE_VERSION_URI = "/rest/api/2/version";
+	static final String SEARCH_URI = "/rest/api/2/search";
+	static final String PROJECT_VERSION_URI = "/rest/api/2/project/%s/version";
+	static final String PROJECT_COMPONENTS_URI = "/rest/api/2/project/%s/components";
+	static final ModuleIteration REST_HOPPER_RC1 = ReleaseTrains.HOPPER.getModuleIteration(Iteration.RC1, "REST");
 
 	@Rule public WireMockRule mockService = new WireMockRule(
 			wireMockConfig().port(8888).fileSource(new ClasspathFileSource("integration/jira")));
@@ -265,7 +265,7 @@ public class JiraConnectorIntegrationTests extends AbstractIntegrationTests {
 	}
 
 	/**
-	 * @see #5
+	 * @see #5, #54
 	 */
 	@Test
 	public void assignTicketToMe() {
@@ -273,13 +273,13 @@ public class JiraConnectorIntegrationTests extends AbstractIntegrationTests {
 		mockService.stubFor(get(urlPathMatching("/rest/api/2/issue/DATAREDIS-302")).//
 				willReturn(json("existingTicket.json")));
 
-		mockService.stubFor(post(urlPathMatching("/rest/api/2/issue/DATAREDIS-302")).//
+		mockService.stubFor(put(urlPathMatching("/rest/api/2/issue/DATAREDIS-302")).//
 				willReturn(aResponse().withStatus(204)));
 
-		jira.assignTicketToMe(new Ticket("DATAREDIS-99999", "", null));
+		jira.assignTicketToMe(new Ticket("DATAREDIS-302", "", null));
 
-		verify(postRequestedFor(urlPathMatching("/rest/api/2/issue/DATAREDIS-302"))
-				.withRequestBody(equalToJson("{\"fields\":{\"assignee\":{\"name\":\"dummy\"}}}")));
+		verify(putRequestedFor(urlPathMatching("/rest/api/2/issue/DATAREDIS-302"))
+				.withRequestBody(equalToJson("{\"update\":{\"assignee\":[ {\"set\":{\"name\":\"dummy\"}} ] }}")));
 	}
 
 	/**