Did you watch Rafael Nadal 2008? He dismantled the greatest player of all time, 6-0 set.
Your stats, Sampras never faced anyone even close to Nadal's 2008 form at the French, we may never see that level on clay again.
The stat in the French open will be higher for Nadal for return games won, because he has given great players 6-0, 6-1, 6-2 sets.
The successful French Open players which had good serves also have a very respectable baseline game, take Soderling for example. But Sampras is nowhere close to these type of players in the baseline department.
Simple play, Nadal stand back, get the ball back into play. From the baseline target Sampras backhand (or forehand really). If Sampras comes to net, it's an easy passing shot.
How else can this match go?