I think Martina's level of play is consistent. What isn't consistent is the performance of her opponents.
Serena Williams - When she's on, she unstoppable. Her serve is huge. She accelerates like a sprinter. She doesn't get tired. When she hits hard, and that's 90% of her groundstrokes in most matches, she hits hard
. And usually, its in. She has a very high rate of unforced errors. But a LOT of those are Serena returning shots no one but her sister or maybe one of the Belgians can even touch. She's big, she's fast, she's sculpture's gift to tennis, but when she's off, she's thoroughly beatable. And Martina beats her. Because Martina's level of play doesn't drop.
Monica - If Monica has it dialed in, Martina's got nothin'. But if Monica slips even a little, Martina's right there. When an elite player is winning by playing their game, no opponent looks good. Think of that 6-1, 6-1 match at OZ s Venus. Sure we know Venus was injured. But she looked BAD. Because Martina got to play HER game. How many players have watched helplessly as Monica Seles launched shot after shot they simply could not reach?
ALL of them.
Kim, Justine, Amelie, Jelena? Hard to judge. None of them usually play well enough to beat Martina. Martina has the head-to-head advantage over all of them. Amelie has won the last two, but Amelie's nerves in a GS final? Bet your house. Go ahead.
The whole top ten CAN play better than Martina. Once in a blue moon. Most of the time they don't, and Martina wins. Jenn and Venus are playing at a higher level now. Martina herself has said as much.
As a singles player, Chris Evert was, perhaps, 99.99% as good as Martina Navratilova. She won her share of majors. Because all she basically had to do was beat Martina, which she knew how to do, even if she couldn't always execute. Right now, Martina Hingis is Chris Evert facing nine Martina Navratilovas. (Well, from various stages of Martina's career.
) Even if you maintain that Martina has just as muich chance as any other top ten player of winning a GS, that doesn't get you past Venus or Jenn. Or Serena or Monica on their good days.
But then you get back to the idea that no one looks good losing to an elite player, playing their game. The only player I've ever seen look good while Serena was playing that way against them was Justine Henin. (It may just be a case of being really fast and using a big backswing on the run. Even Venus doesn't wind up as much as these two on the run. When Justine swings, she uses her whole body. And Serena doesn't so much swing as DETONATE.) Against Martina at Scottsdale, Serena was hitting angles 95% of the tour can't hit at all at full power on a dead run. NO ONE could have looked all that good against that. That result was NOT a function of poor play on Martina's part. Sometimes, Serena plays that way. Mary Pierce was like that too. (And hopefully will be again.) Some days you simply had no chance.