Andy Murray has been warned that he faces a trial by strength against Ernests Gulbis in the second round of Wimbledon, with the Latvian ready to exact revenge for two defeats against Murray last year by outmuscling the British No1.

“Physically, I'm much better than I ever was,” said the lanky World No 74, after revealing the secret of his new mean-looking physique is working out with America fitness guru Pat Etcheberry.

“I've also changed some technical things in my game and I'm feeling much better than last year. I'm hoping to get some more good results here,” added Gulbis, who raced past Italy's Riccardo Ghedin 6-2, 6-4, 6-4 yesterday.

Murray stands in the way of that ambition, and after overcoming American outsider Robert Kendrick 7-5, 6-7, 6-3, 6-4 in gathering gloom on Centre Court last night he conceded that Gulbis could pose a threat.

The 22-year-old Scot said: “I've got a very tough opponent. Gulbis has caused some upsets in the past and is a huge hitter. I'm going to need to be on my game to beat him.”

Kenrick was ranked 76 in the world, just two places below Gulbis, who believes the manner in which he has plummeted from a career high 38 is an unfortunate by-product of Etcheberry's regime.

The 20-year-old, a quarter finalist at last summer's French Open, admitted: “It's been a bad year for me, until now. But I knew it was going to be this way because I did a lot of physical work-outs, more than ever before, and when you do something like that you need a couple of months to let your body adjust to new muscles.

“At first, your game gets worse because you lose your feeling for the ball, you lose feeling for your body. But now I'm getting it back.”

Etcheberry's impressive list of past clients includes Andre Agassi, Pete Sampras, Justin Henin and Monica Seles, golfers Ernie Els and Nick Faldo, and even racing driver Al Unser Jr, two-times winner of the Indy 500.

“He's very good,” said Gulbis. “Now, tennis-wise, I'm getting my form back. Okay, I drove my ranking down a little bit but I need just one good tournament to get my confidence back.”

On paper, those past matches against Murray would suggest that Gulbis might have to wait. At Queen's Club last June Murray triumphed 5-7, 6-1, 6-4 and on the hard court of the St Petersburg Open in October Murray romped to a 6-4, 6-2 win.

Yet Gulbis shruggred those setbacks off, hinting that gamesmanship had a lot to do with the Queen's defeat.

He added: “It was a strange match because I played pretty well. But Murray took a medical time out. Actually, he didn't have anything, but he broke my rhythm and I wasn't an experienced enough player to deal with it. In St Petersburg I was just tired of the season. I tried to play a good match but in my mind I was already on my way home. Now, playing in this tournament, it's going to be a new match.”

Gulbis believes the manner in which he overcame Ghedin will offer Murray a hint of what is to come tomorrow.

The 6ft 3ins right-hander, who made an early exit from Queen's a fortnight ago when he was beaten in straight sets by Spaniard Alberto Martin, said: “In my last couple of matches I didn't play the game I'm used to. I played more defensively, but that's not my style.

“I understand that now and no matter what, I'm going to play aggressively.”

That is what Kendrick did and for a while it seemed as if the 29-year-old, who took Rafael Nadal to five sets at the All England Club three years ago, might have had Murray rattled.

Murray admitted: “I was a bit disappointed to lose the second set, because I had a couple of chances and didn't take them.

“I was expecting him to come out, go for some big shots and he pulled some off at the end of the second set.

“It was a tough match but once I got the breakthrough in the third I felt good. It wasn't an easy match and staying calm was a big part of it because he was coming up with some huge serves at important times.”

Former champion-turned-pundit John McEnroe labelled it a “B” performance from Murray, compared to the “A” grade tennis served up by Roger Federer on the opening day.

And McEnroe was right. Murray admitted he would have to improve to reach the final, saying: “I will have to play great tennis. But I know what I need to do to get there, I'm not going to worry about it yet.”

Perhaps he ought to be just a little concerned. Certainly, Murray will have to be much more energised, much more ruthless on his ground strokes and far more dominant on his serve.
Otherwise, Gulbis might take him by force.