!NoleThumbBy TennisWorld Contributing Editor Andrew Burton

Morning, all.

I may have unintentionally incurred the wrath of Hannah Wilks, longtime commenter (gauloises), Tweeter (@newballsplease) and guest writer under her own name here at TennisWorld. [Aside- throw in an eMail address, and you can see how confusing modern life has become, when you have at least four different names for the same person. But I digress.]

Hannah retweeted this, from tennis writer Stuart Fraser (@stu_fraser): "World No.5, 6, 7, 8 & 10 all out before the quarters in Indian Wells. Can anyone actually see a different top 4 group by end of the year?"

To which my rapid, smart alec response was "No. This has been "Simple answers to your tennis questions.""

Hannah responded "Right. I was forgetting it's blasphemy to question the glory of the present era." The sarcasm in the tweet was like one of A-ha's "Take On Me" charcoal drawn handsreaching out of my IPad screen and smacking me in the chops. I'd momentarily forgotten that Hannah's a Del Potro fan: in my defense, I didn't mean to aim a slap at the big lad from Tandil (or any other posters' favorite players). But I can't lie: I think the odds favor the same group of 4 ATP players atop the rankings come the 2012 WTFs. I don't say it can't change, and if I'm proved wrong, I'll take my medicine. I just think the evidence speaks in favor of the motion.

Let's look at the Djokovic-Almagro quarterfinal yesterday for some supporting data. Djokovic won this match in straight sets, 6-3 6-4: although the scoreline would seem to suggest a close battle, the no 1 seed was on cruise control for most of the match. The most intense battles were reserved for Almagro's service games.  Djokovic won 75% of his service points, Almagro just 56%.  But those are just raw numbers: what was Djokovic doing easily and well that his opponent, scuffling on the edge of the top 10, couldn't match?

First off, the serve: both men have powerful first serves, with Almagro having the edge in raw speed, Djokovic on consistency. The second serve is the first key difference. Djokovic mostly hits with heavy kick, but he can mix location and throws in occasional flat and body serves, so Almagro couldn't get grooved on any one return. On his own second serve, Almagro basically has just one delivery - an 85mph kick serve landing near the middle of the service box. It's a better second serve than (say) Troicki or Seppi hits, but Djokovic, one of the best returners in the game, knows he's going to start 75% of these points in control of the rally.

So, I just mentioned that Djokovic is one of the best returners in the game. Today, his second serve return forced his opponent to take the next ball in retreat. He also made, by my count, at least six amazing stab get returns off 130mph+ first serves. They didn't have to be winners, like "The Shot" (which was off a poorly placed 108mph attempted slice, but no matter, I'm over it, really I am). Even if they split those points evenly, that's three extra points a match - and points mean prizes.

Then there's one more hidden difference, not captured on any stat, so I'll invent one: the Neutral Ball Rallies Won (NBRW) stat.

I've talked about Neutral Ball Rallies before at TW.  My definition of a NBR is one which finds both players in good position behind the baseline, trading at least one groundstroke with the main purpose of not falling into a worse position rather than to hit a winner or  force an error.

That seems a bit wordy, but you know a NBR when you see one. Neither player is having to run hard, shots may be aimed deep but not for the sideline, though one or both players may be mixing up spins, top, back or side.

What happens next? Sooner or later a player makes an unforced error, or a player plays a weak shot (mishit, net cord, short ball). Or one player begins to establish stronger court position, either incrementally or with one forcing shot, and the other player is forced onto the defensive. Sometimes a player can reestablish neutrality, or turn defense into attack: the rally may end with a forced error, a winner, or the attacking player may overdress, sometimes setting up a passing shot for the grateful defender.

Andy Murray has built his career on establishing and winning a high percentage of NBRs. Murray typically aims his topspin groundstrokes into the center of the two imaginary boxes between the service box and the baseline. He can slice, and he can go on the attack, but Murray's basic pattern is get neutral, defend expertly, and wait for mistakes. We'll have to see if this changes under Lendl's coaching: as everyone knows, it's given Murray very good results, but not yet great ones.

Yesterday, I counted 17 neutral ball rallies, and by my count Djokovic won 10, or 59% - coincidentally, almost exactly the same percentage as his margin for the match, 58% to 48%. I'm not suggesting that NBRW correlates 100% with points or matches won, but it's another (geekier, OK) way of saying Djokovic is a steadier player than Almagro. Or, as the man himself put it after the match "Today I had a very powerful ball striker on the opposite side of the net. He's very solid from groundstrokes and has a powerful serve. But I knew that he's inconsistent with that, so I just needed to hang in there, which I did."

When we think of the Big 4 ATP players, their main strength in the last four years, I submit, has been in large part a greater ability to just hang in there. There are occasional matches when a player is apparently touched by the tennis gods - Nadal over Federer at RG 2008 F, or the reverse in WTF London RR last year. More often, as Dolgopolov found against Nadal two days ago, and Almagro today, one thermonuclear winner is outweighed by three stab gets, and by a slow and steady drip-drip-drip of neutral ball rallies going the other way.

Do some players in the 5-20 range play some of these aspects of the game better than the big 4? Sure. I'd bet David Ferrer owns a career NBRW lead over Roger Federer in their H2H, and there's no question that the Spaniard is a better returner than the more storied Swiss. But in their matches, Federer's serves and returns have been better than Ferrer's returns and serves, and Ferrer hasn't been able to get into enough neutral rallies to make that advantage count. More importantly, where career rather than H2H stats are concerned, Federer has been more consistent against other opponents than Ferrer, who is himself a byword for effort and consistency. The Big 4 are great athletes, and great technical players: they also bring enough to each tournament to rack up a season long lead over the pack. And looking at the ATP in March 2012, the odds favor that lead continuing to November.

Which is the long version of my "no" to Hannah and Stuart. Hard to fit into 140 characters.

This month-in, year-in consistency hasn't been found at the top of the WTA for a while, but that may be changing. Victoria Azarenka survived a scare in her first tie at Indian Wells, and now looks a clear favorite for the title. Yesterday's second WTA quarterfinal was a matchup between a veteran top ranked player, Maria Sharapova, and an aspirant, Maria Kirilenko. The higher ranked player prevailed in three sets, in a match of drama and, at one point, controversy. Serving a set up but 4-5 down, Kirilenko left a short ball for a Sharapova putaway. As Sharapova moved up the court to play the ball, there was a rapid "tap-tap-tap" sound: Kirilenko was banging her racquet on the court surface. The umpire, Marija Cicak from Croatia, called "Stop the point! Hindrance. Point to Sharapova." Gutsy call, and 100% right, in my book. Kirilenko held: at the next changeover,  I thought that if she was muttering "Maria, you're ugly inside" she could have been referring to any of the three women on court.

In today's Order Of Play, the ATP quarterfinals are up first: Del Potro-Federer, then Nadal-Nalbandian. Then we have the WTA semi finals: not before 6:00pm, Azarenka plays Kerber, and the night session is capped by Sharapova-Ivanovic.

As always, enjoy today's tennis!

**

Quick programming/self-promotion note: I was interviewed for 45 minutes on all things tennis. This happened on Wednesday morning over the phone with Katie Markin, a local radio journalist for KPTR Progressive Talk AM1450. She'll be broadcasting our segment live on Saturday March 17th (11am PT, 2pm ET). You can stream it live (no podcasts, sorry).