Carlos Moya [Images] of Spain fell by the wayside at the Kingfisher Airlines Open, knocked out by unheralded Juan Martin Del Potro in a men's singles first round match at the CCI courts in Mumbai on Tuesday.

The former world No 1 was outclassed by the 18-year-old Argentine, who is ranked over sixty places below him, 6-3, 6-2.

The upset victory, the second of the day following Austria's Stefan Koubek's 7-6, 6-4 verdict over seventh-seeded Juan Monaco, earned Potro a meeting with Paraguay's Ramon Delgado in the second round.

Delgado led 6-3, 2-1 against Italian David Sanguinetti before the latter retired due to a bout of gastroenteritis.

- Also read: Bopanna makes Moodie sweat

Potro, ranked 106 in the world and playing in just his seventh Tour event, dished out a wonderful exhibition of booming serves and powerful ground strokes to catch Moya off-guard. The Argentine started off with a bang, breaking Moya's serve as early as the second game of the first set, but the Spaniard responded immediately with a break in the next game.

Potro, however, seemed unfazed as he again broke Moya in the fourth game to take a 3-1 lead. His serve never seemed in any danger after that as he wrapped up the first 6-3.

Moya, ranked 43rd, struggled with his serve throughout and it once again let him down in the first game of the second set as Potro took a vital break. The Spaniard hardly threatened the youngster's serves and found it hard to match his powerful groundstrokes.

He looked exhausted and rarely threatened to rally back in the match after the early break in the second set. The crowd tried to lift him with chants of "Come on Moya" but even that didn't help.

Potro then made sure of victory with a break in the seventh game of the second set to take a commanding 5-2 lead.

It was befitting that the tall Argentine finished off the match with an ace to register what he called one of the biggest victories of his career.

The serve statistics tell the real story -- Potro registered a high first serve percentage of 74, while Moya's stood at 48.

As Potro himself agreed after the match, the serve is "my biggest weapon".

"Moya is one of my idols, so this is a very big achievement. Beating a high caliber player like Moya gives me a lot of confidence for the future," said the Argentine after the match.

Potro said his main strategy was to go for the shots and not sit back and defend.

"I didn't want to do the running, but I wanted to make Moya do the running. I just focused on my serve, which is my biggest weapon," he said.

Meanwhile, Moya said it was just one of those days where nothing worked for him.

"I am disappointed, but I don't think he did anything special," said the Spaniard.

Other results (singles first round:
8-Wesley Moodie (South Africa) beat Rohan Bopanna (India) 3-6, 7-6 (6), 6-4
Stefan Koubek (Austria) beat 7-Juan Monaco (Argentina) 7-6 (5), 6-4
Kristian Pless (Denmark) beat Denis Gremelmayr (Germany [Images]) 7-5, 7-5
Ramon Delgado (Paraguay) beat Davide Sanguinetti (Italy [Images]) 6-3, 2-1 (Sanguinetti retired)
Simon Greul (Germany) beat Yen-Hsun Lu (Taiwan) 7-6(4), 6-3

Doubles (first round):
Mario Ancic/Mahesh Bhupathi [Images] beat Akash Wagh/Christopher Marquis 6-0, 6-1

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