Agnieszka “Aggie” Radwanska attained a career-high singles ranking in August of last year. The 19-year-old from Poland cracked the top 10 and brought a No. 9 seed to Melbourne Park. A quarterfinalist in 2008, Radwanska hoped to reduplicate her Australian Open success in 2009. Given a generous draw through her first four rounds, it appeared that one of the WTA Tour’s up-and-comers would be able to reach the round of 8 and stare down Serena Williams in a high-stakes encounter. Hopes were high for a player viewed as a dangerous floater in the women’s field.

In just one match, however, those big dreams were dashed in the 102-degree heat of Melbourne.

A sluggish Radwanska succumbed to the oppressive conditions on Tuesday afternoon, and the woman across the net, Ukraine’s Kateryna Bondarenko, was able to take advantage. The younger sister of fellow tennis professional Alona Bondarenko took down the ninth seed in three sets, 7-6 (7), 4-6, 6-1.

The match unfolded on Show Court No. 2, an outdoor court bereft of the retractable roof that, at the very least, can offer players a brief bit of shade between points. Exposed to the heat, the younger Bondarenko sister and Radwanska would be playing something more than tennis. The two women would be fighting for nothing less than physical survival.

On a day when the No. 4 seed in the women’s tournament, Elena Dementieva, needed three sets to escape the first round, it was clear that the brutally hot weather was leveling the playing field in favor of underdogs. Ideal conditions work to the advantage of shotmakers, but extreme weather rewards the players who possess an extra degree of stamina… even if they lack high-grade weapons. Given that the Australian Open is the first major event of the tennis season, coming just a few weeks after a two-month break, the need for physical fitness is magnified every time the tennis world comes to Melbourne Park. On a terrifically taxing Tuesday, it became painfully apparent that Agnieszka Radwanska needs to develop a better strength and conditioning program.

The difference in this match was indeed conditioning. Bondarenko ran well and covered lots of real estate on the sun-baked surface, whose temperature reached 141 degrees Fahrenheit at one point. Bondarenko’s court coverage was particularly in evidence on the baseline. The Ukrainian displayed superb lateral movement, running smoothly from sideline to sideline and punctuating a number of points with a sensational running two-handed backhand. Bondarenko would typically hit the shot down the line after a baseline-hugging scramble. Radwanska found herself flat-footed in the face of the Bondarenko backhand, evidence that the promising Polish youngster was paralyzed by the heat.

The players who handle severe heat are the ones who don’t have to question their fitness levels during a match. If the mind can focus on tactics and shot selection, the athlete’s body will instinctively produce the right shots and make the right reactions under fire. Those who lack confidence in their level of physical endurance will spend time thinking about their health, and not their tennis. Once the mind loses the ability to focus on the tennis ball and the opponent, the war is lost. This is exactly what happened to Radwanska in her surprising first-round exit. The mind got clouded and cluttered, preventing “Aggie” from hitting more purposeful shots against a dogged opponent.

Radwanska sprayed the ball wide of the sidelines for much of the afternoon, committing 51 unforced errors against just 23 winners. The alarmingly great disparity revealed a player whose footwork was consistently poor. Not only did Radwanska get passed by a bunch of Bondarenko backhands; the Krakow native also forgot to set up her groundstrokes with the baby steps that top players unfailingly manage to make. In all facets of her game and at all spots on the court, Radwanska simply lacked the movement and vitality needed to endure the weather, not to mention her more consistent opponent, who produced 39 winners against only 35 errors. While Bondarenko played strong and steady tennis, Radwanska appeared to be the far more desperate player who wanted to end points as quickly as humanly possible, even if she wasn’t in a winning position on the court. Whenever a player uses a lot of low-percentage shots in an attempt to shorten a match, that’s a classic sign of limited stamina and substandard physical fitness. Bondarenko’s body answered the bell in Australia, while Radwanska never really felt comfortable.

Two more snapshots from this match are worth mentioning. They help to explain why conditioning, more than pure shotmaking, ultimately decided this match.

From a simple numerical standpoint, the first two sets–split by both players–took nearly two hours to complete (1:52). But once the third set arrived, Radwanska’s body was gone. Bondarenko’s 6-1 steamroller consumed just 27 minutes, a quick end to what had been a fiercely-contested battle early on.

The second unique feature of this first-round matchup was that Bondarenko found a way to rob Radwanska of energy. The Ukrainian used a blooper ball that forced Radwanska to either take the ball early inside the baseline, or hit the ball off a high bounce well behind the baseline. Radwanska was correct to take the ball early, but the Polish youngster wasn’t able to do much in these situations. Because of the strain involved in timing this particular shot, Radwanska seemed to focus on merely hitting the ball instead of doing something with it. This is when Bondarenko seized an opening and came up with an impressive passing shot. It was as though Bondarenko was rope-a-doping Radwanska by forcing the ninth seed to hit hard, but without landing a knockout blow. Once Radwanska used up her punches, just like George Foreman, Bondarenko imitated Muhammad Ali and went in for the kill.

The weather was definitely a factor in the early matches on day two of the Australian Open. Agnieszka Radwanska lost to a better opponent on this day, but the No. 9 player in women’s tennis needs to improve to the extent that her footwork–and her mind–won’t break down in what is quite literally the heat of battle.