After a few weeks honing their skills in tournaments from Auckland to Doha, all attention has turned to the crowned jewel of the region as play began in Melbourne at the Australian Open. And on the first day of the first major of the season, it took little time before a major upset occurred.

In the first match in Rod Laver Arena, Shelby Rogers upset 4th-seeded Simona Halep 6-3, 6-1. The American won the match in routine fashion riding her effective serve.  Halep could only muster one break opportunity in the match which was thwarted by the world no. 52.

Meanwhile, Halep won just 58 percent of her first serve points and saw her serve broken four times in the match.

“The biggest thing I took away from that was just that I can compete with the top players in the world, and I’m good enough,” Rogers said. “I think I played great today, trying to be aggressive going out there.”

Halep took a medical timeout between sets and revealed afterward that she was dealing with tendinitis in her left leg that hampered her movement.

Elsewhere in the women’s draw, Venus Williams advanced past Kateryna Kozlova 7-6, 7-5 and will move on to the second round.

The veteran, who will turn 37 this year, survived the heat and the endurance test in a match that lasted nearly two hours.

“It's never easy playing the first round,” said Williams. “I was just trying to find my rhythm. She didn't make it easy so I'm happy to be through.”

Venus, the oldest player in the draw, is competing in her 73rd grand slam.

Meanwhile, 7th-seeded Garbine Muguruza overcame an injury and a slow start to defeat Marina Erakovic of New Zealand 7-5, 6-4.  The Spaniard needed a medical timeout after the first set to treat an apparent foot injury.

The 23-year old overpowered Erakovic with big groundstrokes and her power game to advance. She addressed her injury afterward, “There was not like a specific moment where I felt it, honestly,” she said. “I took a medical timeout and became a little bit unfocused on the court, and it took me a couple of games to get into the match again. It was good that I could turn it around in that second set, even though I was 4-1 down.”