By Tom Fordyce

Gilbert (left) in his days as Agassi's coach

He did it with Andre Agassi and now he's doing the same with Andy Roddick.

Dubbed by Agassi "the greatest coach of all time", Brad Gilbert is the man who revolutionised tennis coaching.

Agassi won six Grand Slam titles under his tutelage, plus a gold medal at the 1996 Olympics, making him the only male tennis player in history to have won all four Grand Slam singles titles and Olympic gold.

Roddick linked up with Gilbert at the start of this month. Already the critics are noticing a difference in his game.

"As far as Roddick is concerned, Brad has come along at a great time," says 1987 Wimbledon champion Pat Cash.

"Andy was ready to break in, but he used to spit the dummy a lot and needed to tighten up on the mental thing. It's the finer things - the tactics, getting focused - and Gilbert seems to have helped."

Three-time Wimbledon champion Boris Becker says the importance to a player of a good coach cannot be underestimated.

"We can see how Lleyton Hewitt is struggling without his old coach Jason Stoltenberg," he says. "He's nowhere near where he was a month ago.

Gilbert in his playing days

"Roddick was always talented, but Brad Gilbert is one of the most experienced coaches out there. If you've worked with Andre Agassi for six years, you know a thing or two about tennis."

Gilbert himself was a successful yet never world-beating player, winning 20 singles titles and almost �4m in prize money in a career that stretched from 1982 until injuries called a halt in 1994.

He was once ranked as high in the world as fourth (1990) and was never outside the top 25 from 1984 to 1991.

But it was his method of play, rather than his level of success, that gave the clearest indication that here was tennis thinker of rare acumen.

After one particularly gritty win, the New York Times newspaper coined the phrase 'winning ugly' to describe Gilbert's success. It stuck to him like jam to a baby's face.

"People see me and I don't hit the ball that hard. They say, 'How's he winning?'" Gilbert said at the time.

Gilbert, who used tactics and scouting to defeat his opponents, began a player-coaching role with Agassi at the Lipton Championships in 1994.

Agassi was once asked for the best single piece of advice his coach had given him.

"Brad believes that 5% of the time our opponent is in the zone and you will not win," he said. "Five per cent of the time you get in the zone and can't lose.

"The other 90% of the time it's up for grabs; there is a way to win. You've just got to figure it out."

Gilbert eventually co-wrote a book on his methods - called, unsurprisingly, 'Winning Ugly' - and it became a favourite with other Tour players.

"I like to break down the opponent into strengths and weaknesses," he explains. "Right now, I think about what Andy can do. I look through his eyes and see what he can capitalise on.

"It's all about finding a way, every other day, to win three sets. You don't get caught up in this whole hoopla about what's going on - you just take care of business.

"It's not about thinking about winning Wimbledon, it's about trying to get better. Andre, even at 33, still thinks every shot he plays could be better.

"Andy going to be unbelievable, He's sixth in the world, and he's nowhere near where he's going to be in five years time."