Saha helped create Cristiano Ronaldo's goal in the draw and Ferguson told MUTV: "I had the strongest bench that we've had all season, that's encouraging for us.
"The lads who have been playing all this time have been fantastic and we are very proud of them. But we can now alternate our teams a little bit better."
"Louis Saha made a marvellous contribution when he came on," praised Sir Alex.
"He made a great pass for the goal to Evra who squared it for Ronaldo. At that point, I thought we were home and dry."