diff --git a/src/a2a/client/base_client.py b/src/a2a/client/base_client.py
index 657e78ac..eadfdb62 100644
--- a/src/a2a/client/base_client.py
+++ b/src/a2a/client/base_client.py
@@ -1,9 +1,6 @@
 from collections.abc import AsyncGenerator, AsyncIterator, Callable
-from types import TracebackType
 from typing import Any
 
-from typing_extensions import Self
-
 from a2a.client.client import (
     Client,
     ClientCallContext,
@@ -48,19 +45,6 @@ def __init__(
         self._config = config
         self._transport = transport
 
-    async def __aenter__(self) -> Self:
-        """Enters the async context manager, returning the client itself."""
-        return self
-
-    async def __aexit__(
-        self,
-        exc_type: type[BaseException] | None,
-        exc_val: BaseException | None,
-        exc_tb: TracebackType | None,
-    ) -> None:
-        """Exits the async context manager, ensuring close() is called."""
-        await self.close()
-
     async def send_message(
         self,
         request: Message,
diff --git a/src/a2a/client/client.py b/src/a2a/client/client.py
index cad49173..b698a769 100644
--- a/src/a2a/client/client.py
+++ b/src/a2a/client/client.py
@@ -3,10 +3,13 @@
 
 from abc import ABC, abstractmethod
 from collections.abc import AsyncIterator, Callable, Coroutine
+from types import TracebackType
 from typing import Any
 
 import httpx
 
+from typing_extensions import Self
+
 from a2a.client.middleware import ClientCallContext, ClientCallInterceptor
 from a2a.client.optionals import Channel
 from a2a.types.a2a_pb2 import (
@@ -106,6 +109,19 @@ def __init__(
         self._consumers = consumers
         self._middleware = middleware
 
+    async def __aenter__(self) -> Self:
+        """Enters the async context manager."""
+        return self
+
+    async def __aexit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_val: BaseException | None,
+        exc_tb: TracebackType | None,
+    ) -> None:
+        """Exits the async context manager and closes the client."""
+        await self.close()
+
     @abstractmethod
     async def send_message(
         self,
@@ -217,3 +233,7 @@ async def consume(
             return
         for c in self._consumers:
             await c(event, card)
+
+    @abstractmethod
+    async def close(self) -> None:
+        """Closes the client and releases any underlying resources."""