Agassi, himself said that Berasategui has the best forehand of anyone in the world when "on" after getting single-handedly slobber-knocked by this one shot and ONLY shot that Berasategui had at the Australian Open.
What made Berasategui's forehand so good was that he could hit it all day without missing and seemingly at near or max possible velocity and spin. His motion was actually quite compact, and VERY difficult to read the direction of the ball. It was like he drew the ball in to him like a matador, then cracked his wrist like a gun, and the direction of the ball was a mystery. Could whack a cold winner at any time, by adding a little extra bit of panache to his wrist snap. His body preparation always looked the same since it wasn't as total body reliant as others, say Kafelnikov or Srichiphan, for example, of whom it was obvious when they were/are gearing up for an all or nothing forehand, hence, you could better ready yourself to brace for it. Seemed like he just relied on his fine motor skills and had total control over them in that split second, and make no mistake it was a split second.
As Goran put it, "his forehand is like a gun." That's the best way to describe how it went off. One quick, itchy trigger finger for sure, and he RARELY missed his target.
Of the guys on the list, you have to factor that they all had game beyond just a big forehand...even Courier who had a forcing first serve and unrivaled fitness/mental toughness.
Berasategui, however, to me was a legitimate top twenty player, borderline top ten player. On his "hot" days, he could take anybody out. As Courier put it, after facing Berasategui for the first time (0-2 lifetime), "He beat the Merv Hagler out of me."
You have to respect his forehand and what he did with it all that much more when you realize that he made it as close to the top as he did based on this ONE shot alone. I don't think you can say that about anybody else who relied soley on one shot to get so far. Also, I think forehand was a little different from other big forehands, in that his had a peculiar, funky, kind of a "reverse spin" on the ball as Chang put it in his press conference after drastically reversing his fortunes against Berasategui mid-match at the Lipton on the brink of defeat. In this match, Berasategui started off by beating the living TAR out of Chang with his forehand, but then on the edge of defeat Chang finally got the sense to change his strategy. He decided to try and keep the ball away from Berasategui's forehand at all costs. It worked like a charm, he stole the second set then ran away with the third. Obviously, keeping the ball away from Berasategui's forehand was easier said than done, but it COULD be done.
This was its fatal flaw, in my opinion. Berasategui's forehand could be exposed by drawing him SO wide on the backhand side, that he would have no chance to cover a running forehand with any real zest...fast as he was. He also could get tired from having to just run around his backhand SO much more than anybody else in the game had too...once this happened, as Bliip said after beating him 6-love in the third of one of their matches; the difference is that he only *just* has his forehand, once he gets tired, that's it, it's over, finito. There is NO inbetween for him to compete with.
Also, Berasategui was vulnerable, even on clay, to a high kick serve to his backhand. It was one of the great unguarded weaknesses by a top or near top player that I can ever recall. John McEnroe: "It's his achilles heel." Factor the ingredients. Short guy, high bouncing clay, 6'6" Todd Martin charging the net, hitting kick serves to the short guy's pseudo one/two hander hit from a WEAK platform...you're asking for trouble.
This is how Martin of all people dismantled Berasategui in the finals of Barcelona, and Martin didn't even have more than a slightly average kick serve in my opinion.
Berasategui was just too dangerous and just too vulnerable at the same time for his own good. Ultimately, I believe this is what led to early burn-out with him; not necessarily injury.
As McEnroe put it after watching Berasategui go down rather meakley and half-heartedly against Arazi at the French near the end of his career, "He just doesn't seem to have the same energy I'm used to seeing from the little guy." Indeed, in this match, Arazi played great, but it was like Berasategui was a step slow, sluggish, and just like his mind wasn't quite there. Like a robot was playing in place of the once fresh, strawberry eyed youngster with the zest for life. As McEnroe put it, to paraphrase, "He's a very outgoing, personable little guy. All the guys in the locker room seem to love him." LOVE his backhand, HATE his forehand, keep the smile

.
He brought a positive vibe to the court I think. He competed hard, and kind of reminded me of his generation's Paradorn Srichiphan. One of those fringe top players who every now and again surprise you with the BIG and convincing upset, but mostly remain as dangerous but can't quite get over the hump players. Both also seemed to have that great locker room raport with the guys, and just were all-around likeable fellows who for the most competed hard, albeit missing that EDGE that so often separates the Courier, the Muster, the ANIMALS, of the world from the kittens. In other words, they both lacked a killer instinct, but also were not tankers.
Great sportsmen though, and never the breakneck type of competitors to scrub out a line, a la Connors...in old age, Mr. Sanctimony himself.
With Berasategui, you always got the sense that he seemed to really appreciate what he had.
He retired, burned out and injured (but me thinks mostly just pre-mature burn-out...the nature of the beast when you employ "extreme" techqniques...VERY difficult to keep-up if you lose just a little bit of your drive, NO in between with extreme techniques as you can't really stroke the ball when you're feeling lazy or just block it back, these techniques require full-out flailing to be effective, "all or nothing" techniques/strokes), and became an insurance agent I believe in his parent's company.
He was one of those guys who added to the colorful and diversified cast of mid-90s characters, in my opinion.
All raggedy-taggedy in appearance, but, I'd be darned if he couldn't tag you with a forehand!
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As far as Muster goes, well, I don't think he was placed on the list, because his forehand wasn't his signature shot off the ground. Muster's groundies, both backhand and forehand, taken as a whole were his deal, the total, relentless package off the ground. It's not that his forehand wasn't VERY good, it's that it wasn't quite unique enough to ever become of the signature weapons in the game as it was with the above guys. Actually, I would say Guga's in the same category. To me, he doesn't belong on the list either, since to me, it was he won primarily because his backhand was so DEVASTATINGLY dangerous, which made his forehand all the more effective. Taken by itself in isolation, however, I wouldn't say Kuerten's forehand ever approached his "signature" shot level proportions, which I think is the key distinction here. Not, that it wasn't a GREAT shot in and of itself. Just not his best shot is all.
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Actually, as far as "best forehand of all time" goes, I don't think you can make that distinction. There are to me, different kinds of best. If you're talking about the best *topspin*...claycourt stylized/optimized...forehand of all time, then Bliip, Vilas' words, "Greatest *claycourt* forehand of all time." The technique was very specifically optimized for clay and nothing but clay, not that it couldn't be effective outside of clay, just that it ran "hot or cold" depending the day, per Jeff Tarango's own formal scouting report.
Lendl to me had the most VERSATILE forehand of all time, in that it was neither overspun, nor underspun, neither taken too early, nor too far behind the baseline, etc. Very much a PRECISE forehand, that he bludgeoned with the weighted, sledge hammer tip of his racket. This kind of forehand would work well on any surface, conservative grip but with a bit of a loop to his swing so as to not hit TOO flat like Connors. It's a mistake to think non-extreme techqniue doesn't work on clay. It does, just look at Medvedev and Kafelnikov from the last generation. Since when does having MORE time to set-up for every shot a handicap? IF you're groundies are consistent and smooth, then the less extreme grips can be used to great advantage as well, as they provide an imminently STABLE hitting platform. Just look at Pioline, his forehand looked almost more comfortable on clay than on faster surfaces even though it's very traditional technique. Why? He used the extra time to his advantage, which allowed him to STROKE to the ball to his heart's content and build a good rhythm, which was always so critical to his success...not to mention, Pioline's forehand allowed him to coast a bit more than say Berasategui could...a FAR less fatiguing method of hitting the ball.
Berasategui to me had a wild card forehand for all surfaces and under all conditions and against all opponents except fast indoor carpet or grass.
Perhaps, as Arazi described him after having been *owned* by him pre-burnout phase, "He's a real crocodile."