openClientSockets.add(sslSocket)

          if (protocolNegotiationEnabled) {
            Platform.get().configureTlsExtensions(sslSocket, null, protocols)
          }

          sslSocket.startHandshake()

          // Wait until after handshake to grab the buffered socket
          socket = MockWebServerSocket(sslSocket)

          if (protocolNegotiationEnabled) {

      if (connectionSpec.supportsTlsExtensions) {
        Platform.get().configureTlsExtensions(sslSocket, address.url.host, address.protocols)
      }

      // Force handshake. This can throw!
      sslSocket.startHandshake()
      // block for session establishment
      val sslSocketSession = sslSocket.session
      val unverifiedHandshake = sslSocketSession.handshake()