diff --git a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/client/RestTemplateBuilderTests.java b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/client/RestTemplateBuilderTests.java
index cd87b9a861..0c8a13315f 100644
--- a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/client/RestTemplateBuilderTests.java
+++ b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/client/RestTemplateBuilderTests.java
@@ -16,6 +16,7 @@
 
 package org.springframework.boot.web.client;
 
+import java.time.Duration;
 import java.util.Collections;
 import java.util.Set;
 import java.util.function.Supplier;
@@ -60,6 +61,7 @@ import static org.springframework.test.web.client.response.MockRestResponseCreat
  * @author Stephane Nicoll
  * @author Phillip Webb
  * @author Andy Wilkinson
+ * @author Dmytro Nosan
  */
 public class RestTemplateBuilderTests {
 
@@ -390,7 +392,7 @@ public class RestTemplateBuilderTests {
 	}
 
 	@Test
-	public void customizerShouldBeAppliedInTheEnd() {
+	public void customizerShouldBeAppliedAtTheEnd() {
 		ResponseErrorHandler errorHandler = mock(ResponseErrorHandler.class);
 		ClientHttpRequestFactory requestFactory = new HttpComponentsClientHttpRequestFactory();
 		this.builder.interceptors(this.interceptor)
@@ -439,7 +441,7 @@ public class RestTemplateBuilderTests {
 	public void connectTimeoutCanBeConfiguredOnHttpComponentsRequestFactory() {
 		ClientHttpRequestFactory requestFactory = this.builder
 				.requestFactory(HttpComponentsClientHttpRequestFactory.class)
-				.setConnectTimeout(1234).build().getRequestFactory();
+				.setConnectTimeout(Duration.ofMillis(1234)).build().getRequestFactory();
 		assertThat(((RequestConfig) ReflectionTestUtils.getField(requestFactory,
 				"requestConfig")).getConnectTimeout()).isEqualTo(1234);
 	}
@@ -448,7 +450,7 @@ public class RestTemplateBuilderTests {
 	public void readTimeoutCanBeConfiguredOnHttpComponentsRequestFactory() {
 		ClientHttpRequestFactory requestFactory = this.builder
 				.requestFactory(HttpComponentsClientHttpRequestFactory.class)
-				.setReadTimeout(1234).build().getRequestFactory();
+				.setReadTimeout(Duration.ofMillis(1234)).build().getRequestFactory();
 		assertThat(((RequestConfig) ReflectionTestUtils.getField(requestFactory,
 				"requestConfig")).getSocketTimeout()).isEqualTo(1234);
 	}
@@ -457,7 +459,7 @@ public class RestTemplateBuilderTests {
 	public void connectTimeoutCanBeConfiguredOnSimpleRequestFactory() {
 		ClientHttpRequestFactory requestFactory = this.builder
 				.requestFactory(SimpleClientHttpRequestFactory.class)
-				.setConnectTimeout(1234).build().getRequestFactory();
+				.setConnectTimeout(Duration.ofMillis(1234)).build().getRequestFactory();
 		assertThat(ReflectionTestUtils.getField(requestFactory, "connectTimeout"))
 				.isEqualTo(1234);
 	}
@@ -465,8 +467,8 @@ public class RestTemplateBuilderTests {
 	@Test
 	public void readTimeoutCanBeConfiguredOnSimpleRequestFactory() {
 		ClientHttpRequestFactory requestFactory = this.builder
-				.requestFactory(SimpleClientHttpRequestFactory.class).setReadTimeout(1234)
-				.build().getRequestFactory();
+				.requestFactory(SimpleClientHttpRequestFactory.class)
+				.setReadTimeout(Duration.ofMillis(1234)).build().getRequestFactory();
 		assertThat(ReflectionTestUtils.getField(requestFactory, "readTimeout"))
 				.isEqualTo(1234);
 	}
@@ -475,7 +477,7 @@ public class RestTemplateBuilderTests {
 	public void connectTimeoutCanBeConfiguredOnOkHttp3RequestFactory() {
 		ClientHttpRequestFactory requestFactory = this.builder
 				.requestFactory(OkHttp3ClientHttpRequestFactory.class)
-				.setConnectTimeout(1234).build().getRequestFactory();
+				.setConnectTimeout(Duration.ofMillis(1234)).build().getRequestFactory();
 		assertThat(ReflectionTestUtils.getField(
 				ReflectionTestUtils.getField(requestFactory, "client"), "connectTimeout"))
 						.isEqualTo(1234);
@@ -485,7 +487,7 @@ public class RestTemplateBuilderTests {
 	public void readTimeoutCanBeConfiguredOnOkHttp3RequestFactory() {
 		ClientHttpRequestFactory requestFactory = this.builder
 				.requestFactory(OkHttp3ClientHttpRequestFactory.class)
-				.setReadTimeout(1234).build().getRequestFactory();
+				.setReadTimeout(Duration.ofMillis(1234)).build().getRequestFactory();
 		assertThat(ReflectionTestUtils.getField(
 				ReflectionTestUtils.getField(requestFactory, "client"), "readTimeout"))
 						.isEqualTo(1234);
@@ -497,7 +499,7 @@ public class RestTemplateBuilderTests {
 		this.builder
 				.requestFactory(
 						() -> new BufferingClientHttpRequestFactory(requestFactory))
-				.setConnectTimeout(1234).build();
+				.setConnectTimeout(Duration.ofMillis(1234)).build();
 		assertThat(ReflectionTestUtils.getField(requestFactory, "connectTimeout"))
 				.isEqualTo(1234);
 	}
@@ -508,7 +510,7 @@ public class RestTemplateBuilderTests {
 		this.builder
 				.requestFactory(
 						() -> new BufferingClientHttpRequestFactory(requestFactory))
-				.setReadTimeout(1234).build();
+				.setReadTimeout(Duration.ofMillis(1234)).build();
 		assertThat(ReflectionTestUtils.getField(requestFactory, "readTimeout"))
 				.isEqualTo(1234);
 	}
@@ -524,6 +526,46 @@ public class RestTemplateBuilderTests {
 				.isInstanceOf(BufferingClientHttpRequestFactory.class);
 	}
 
+	@Test
+	@SuppressWarnings("deprecation")
+	public void deprecatedReadTimeout() {
+		ClientHttpRequestFactory requestFactory = this.builder
+				.requestFactory(SimpleClientHttpRequestFactory.class).setReadTimeout(1234)
+				.build().getRequestFactory();
+		assertThat(ReflectionTestUtils.getField(requestFactory, "readTimeout"))
+				.isEqualTo(1234);
+	}
+
+	@Test
+	@SuppressWarnings("deprecation")
+	public void deprecatedConnectTimeout() {
+		ClientHttpRequestFactory requestFactory = this.builder
+				.requestFactory(SimpleClientHttpRequestFactory.class)
+				.setConnectTimeout(1234).build().getRequestFactory();
+		assertThat(ReflectionTestUtils.getField(requestFactory, "connectTimeout"))
+				.isEqualTo(1234);
+	}
+
+	@Test
+	public void readTimeoutShouldBeIgnored() {
+		ClientHttpRequestFactory requestFactory = this.builder
+				.requestFactory(SimpleClientHttpRequestFactory.class)
+				.setReadTimeout(Duration.ofSeconds(5)).setReadTimeout(null).build()
+				.getRequestFactory();
+		assertThat(ReflectionTestUtils.getField(requestFactory, "readTimeout"))
+				.isEqualTo(-1);
+	}
+
+	@Test
+	public void connectionTimeoutShouldBeIgnored() {
+		ClientHttpRequestFactory requestFactory = this.builder
+				.requestFactory(SimpleClientHttpRequestFactory.class)
+				.setConnectTimeout(Duration.ofSeconds(5)).setConnectTimeout(null).build()
+				.getRequestFactory();
+		assertThat(ReflectionTestUtils.getField(requestFactory, "connectTimeout"))
+				.isEqualTo(-1);
+	}
+
 	public static class RestTemplateSubclass extends RestTemplate {
 
 	}