I was watching Courier vs Borg on tennis channel today. They've definitely lost a step with age but they still got the court smarts. Yet, it still seems like there is a very large gap between the retired pros and the top players on the tour today. I was wondering.... Could these guys still beat anyone in the top 100? What level of tennis are Courier and Borg playing now? Are they still 7.0? 6.0? 5.0+?