No one I can think of. Roger's 236 consecutive weeks at #1 is all the proof you need for that answer. Sampras lost the #1 ranking quite a few times, and finished the year #1 after some lucky breaks a couple times. That doesn't take away from his accomplishments, but it underscores the totality and rarity of Roger's dominance, and suggests that Rafa shouldn't expect to match Roger's run from 2004 to 2007.