diff --git a/src/ruby/qps/proxy-worker.rb b/src/ruby/qps/proxy-worker.rb
index ae7006e7d60..478370c5bf2 100755
--- a/src/ruby/qps/proxy-worker.rb
+++ b/src/ruby/qps/proxy-worker.rb
@@ -31,9 +31,10 @@ require 'src/proto/grpc/testing/services_services_pb'
 require 'src/proto/grpc/testing/proxy-service_services_pb'
 
 class ProxyBenchmarkClientServiceImpl < Grpc::Testing::ProxyClientService::Service
-  def initialize(port, c_ext)
+  def initialize(port, c_ext, php_client_bin)
     @mytarget = "localhost:" + port.to_s
     @use_c_ext = c_ext
+    @php_client_bin = php_client_bin
   end
   def setup(config)
     @config = config
@@ -44,11 +45,11 @@ class ProxyBenchmarkClientServiceImpl < Grpc::Testing::ProxyClientService::Servi
     # TODO(vjpai): Support multiple client channels by spawning off a PHP client per channel
     if @use_c_ext
       puts "Use protobuf c extension"
-      command = "php -d extension=" + File.expand_path(File.dirname(__FILE__)) + "/../../php/tests/qps/vendor/google/protobuf/php/ext/google/protobuf/modules/protobuf.so " + "-d extension=" + File.expand_path(File.dirname(__FILE__)) + "/../../php/ext/grpc/modules/grpc.so " + File.expand_path(File.dirname(__FILE__)) + "/../../php/tests/qps/client.php " + @mytarget
+      command = "php -d extension=" + File.expand_path(File.dirname(__FILE__)) + "/../../php/tests/qps/vendor/google/protobuf/php/ext/google/protobuf/modules/protobuf.so " + "-d extension=" + File.expand_path(File.dirname(__FILE__)) + "/../../php/ext/grpc/modules/grpc.so " + File.expand_path(File.dirname(__FILE__)) + "/" + @php_client_bin + " " + @mytarget
     else
       puts "Use protobuf php extension"
-      command = "php -d extension=" + File.expand_path(File.dirname(__FILE__)) + "/../../php/ext/grpc/modules/grpc.so " + File.expand_path(File.dirname(__FILE__)) + "/../../php/tests/qps/client.php " + @mytarget
-    end	
+      command = "php -d extension=" + File.expand_path(File.dirname(__FILE__)) + "/../../php/ext/grpc/modules/grpc.so " + File.expand_path(File.dirname(__FILE__)) + "/" + @php_client_bin + " " + @mytarget
+    end
     puts "Starting command: " + command
     @php_pid = spawn(command)
   end
@@ -128,7 +129,8 @@ end
 
 def proxymain
   options = {
-    'driver_port' => 0
+    'driver_port' => 0,
+    'php_client_bin' => '../../php/tests/qps/client.php'
   }
   OptionParser.new do |opts|
     opts.banner = 'Usage: [--driver_port <port>]'
@@ -138,6 +140,10 @@ def proxymain
     opts.on("-c", "--[no-]c_proto_ext", "Use protobuf C-extention") do |c|
       options[:c_ext] = c
     end
+    opts.on("-b" "--php_client_bin [FILE]",
+        "PHP client to execute; path relative to this script") do |c|
+      options['php_client_bin'] = c
+    end
   end.parse!
 
   # Configure any errors with client or server child threads to surface
@@ -146,7 +152,7 @@ def proxymain
   s = GRPC::RpcServer.new
   port = s.add_http2_port("0.0.0.0:" + options['driver_port'].to_s,
                           :this_port_is_insecure)
-  bmc = ProxyBenchmarkClientServiceImpl.new(port, options[:c_ext])
+  bmc = ProxyBenchmarkClientServiceImpl.new(port, options[:c_ext], options['php_client_bin'])
   s.handle(bmc)
   s.handle(ProxyWorkerServiceImpl.new(s, bmc))
   s.run