Lendl desperately wanted to become a pro golfer from what I remember after he retired, he really tried hard, but just was never/could never get good enough. So definitely Scott Draper's level of play in golf is pretty astounding. It's always a rarity to find a person talented enough to play at pro level in two separate sports--quite an astonishing accomplishment really. Draper was actually a very talented tennis player too, and was thought of by many in Australia as their next big star growing up, much more so than someone like Rafter ever was. But alas in the end, he was raised in the Aussie tradition that says serve and volley, all-court play is the only way to play. Problem for him became, I suppose, that he just didn't grow...enough. He was like 5'9-10" or so, and like Todd Woodbridge who was also thought to be the next great Aussie growing up, both guys simply played too classical a game for their height. You just can't make it all the way to the top in pro tennis at that height playing that way. It's a testament to their natural ability that they got as far as they did. Draper was quite injury prone and the death of his wife really set him back, but there was a period where he was really establishing himself as a solid middle of the run guy who could give anyone in the world a run on his best day. All his strokes were very smooth and natural, and his transitions from every part of the court to another, equally smooth and natural. He was also a great sportsman, one of the most liked guys on tour, and just came out to play every day and you knew he wasn't going to tank on you, and every fan knew that he was going to give you all he had that day, he wasn't going to slap you in the face and insult you like say, oh...RIOS.
Hard to say, but had he been brought up on clay or in America, and not steered to be a net rusher in the great Aussie tradition, I think he would have definitely been a top twenty player, and quite possibly top ten or even more at some point. He just didn't have a pro appropriate frame to play that way at the pro level, but I think it was clear in watching him that he really did have talent...just the wrong game, and short limbs for it. Had his size been taken into consideration, I think he would have been much better off with at least a semi-western grip, baseline only game.
Rafter on the other hand, you could tell was definitely not as naturally talented as Draper, none of his strokes looked particularly smooth, everything looked muscled, grunted at, labored, like someone who had to really work hard at every shot he had, yet on the other hand, he was a primo jock athlete, but more importantly unlike Draper, he had the primo jock BUILD. In other words, he was tall enough to play that way. Both gave it their all and were great guys, but other than that I'm not really sure what Rafter did better than Draper that couldn't/wouldn't be attributed to him basically just being taller than him. Oh well, I guess that's just the way pro sports are. Too bad tennis doesn't have pound for pound, size-class distinctions, like combat sports as there are a lot of top class junior talents that never make it at the pro level due to no other reason other than not being tall enough.