No, just no. At his best/when he gets a period of decent health, Del Potro can compete with the top 4 on even terms - check his recent match vs Djokovic in IW. He did not blow Djokovic off the court, he simply outplayed and outmanouevered him, Nole actually had more winners. What I mean by this is his usual point construction is enough to hang with those guys given a decent period of good health.
Wawrinka needs to absolutely redline his game to have a chance to beat them and even then often comes up short mentally. Del Potro is miles ahead of Wawrinka, I can't believe this is a discussion. Injured Del Potro is still more of a threat to the top players than Wawrinka any day.
Yet a decent period of good health for Del Potro is seldom. What is more ludicrous is you openly come out and say he is easily
the fifth best player in the world. Sure, I'll agree to that if he, you know, stays consistent. Making the Indian Wells final was exceptional and I thoroughly enjoyed his victories over Murray and Djokovic. Two weeks later, he has an early-round exit at Miami. You just don't know what you'll get from Delpo. With Ferrer, there is an underlying sense of certainty.