MELBOURNE, Australia(AP) With his wrist aching and temper fraying, Juan Martin del Potro turned to his strength.
The U.S. Open champion fired 21 aces - one at 135 mph - to overpower American Michael Russell 6-4, 6-4, 3-6, 6-2 in the first round of the Australian Open on Monday.
Del Potro, a 6-foot-6 Argentine seeded No. 4, played with his right wrist and forearm taped to stave off a recurrence of tendinitis.
``I don't feel 100 percent,'' he said after the 3-hour match.
Del Potro, with his big serves and bigger forehands, was unheralded until his win over Roger Federer at the U.S. Open. He ended Federer's streak of five straight U.S. Open titles and beat Rafael Nadal en route to the final, making him the only man to defeat both players at a Grand Slam event.
On Monday, del Potro's opponent measured all of 5-foot-8. Russell, ranked 90th, described the challenges of facing a player with del Potro's wingspan.
He's creating angles that I'm just not able to create,'' Russell said.He's able to cover the court without taking as many steps. He has more power as well because he has more leverage.''
Russell said the higher bounce coming off del Potro's serve forced him to stand near the wall to receive serves - making it harder for him to recover.
``That's giving up way too much ground for me to do that,'' he said.
Russell faced some height jokes from spectators, but he won over the crowd with his speed and acrobatics. At one point the 31-year-old American lunged into a split to make a forehand winner and break del Potro's serve midway through the second set.
The crowd at the Hisense Arena, the tournament's second show court, turned on the Argentine and applauded his errors after his long, angry exchange with the chair umpire in the sixth game of the third set.
Russell had hit a return that del Potro thought was out, but the Argentine whacked it back across the net anyway and was surprised when Russell returned it for a winner. Del Potro wanted to challenge the call but the chair umpire ruled that he had waited too long.
The umpire said I took too much time to call the challenge,'' del Potro said.I tried to explain to her I just hit the ball and then saw the mark and called the challenge.
``But she said you can't do that. After that, I was disappointed.''
After a heated exchange, del Potro resumed serving and vented his frustration by unleashing the 135 mph ace.
At the Shanghai Masters in October, del Potro retired in the second round because of right wrist tendinitis. The problem reappeared last week, when he cited the wrist injury as the reason for withdrawing from an exhibition tournament at Kooyong, a warm-up for the Australian Open. At the time, del Potro's agent, Ugo Colombini, said he did not believe the injury was serious.
Next up, del Potro faces the winner of a first-round match between Arnaud Clement of France and American James Blake.