Greatest player ever?

I was flipping the channels the other morning at about 3:30 as I always do. I stumbled across the Australian Open with top-ranked Roger Federer tied with his opponent 3-3 in the fifth set.
I know a lot of folks don't like tennis. But, anyone who likes sports and competition, I defy you to stumble into this match at this point and not watch it.
I'm not hugely interested in men's tennis. I just assumed, because the tennis people tell me, that Federer is the greatest player of all time. I've never really watched for myself, though.
Okay, now I understand what those folks are talking about.
The man was brilliant, especially on big points. He waited for his opportunity and when his big-serving opponent slipped up, the match was over.
Just like that.
It was a great match. More importantly, I got to see why Federer is the most dominant athlete in the world at his sport.
While I'm in the tennis mode, I watched Serena Williams lose to Jelena Jankovic in the quarterfinals. It bothers me that anytime one of the Williams sisters lose, the American announcers question their effort, heart, desire, preparation, etc.
Everyone can have a bad day. But, apparently that's not allowed for the Williams sisters.
Just as appalling is the lack of respect given to Jankovic, who played some darn good tennis, yet was given little to no credit for the biggest win in her career.
I don't watch tennis often and, after listening to the American slanted coverage, I remember why I don't get more into it.
Sorry, I'll talk about basketball next time.