The Grand Slam season began on Monday in sunny Melbourne with a number of high seeds in action.  Here is a look at some of the interesting matches from the early session.

Serena Williams Advances

Entering the Australian Open, there was a lot of discussion about the state of Serena Williams’ game. She hadn’t played a match since losing at the U. S. Open and had recently fought an injury that forced her out of Hopman Cup. However, Williams would advance after a challenge from Camila Giorgi, 6-4 7-5.

In 2015, Williams had a tendency to start slow at the majors, but she jumped out to a quick lead over a scrappy Giorgi on Monday. The Italian showed grit, fought back into the match, and continued to push the top seed in the second set. But as she often does, Williams was clutch on the important points and would find enough to advance into the second round. Giorgi was a difficult test for much of the match, but Williams would close on an exclamation point with a big service game that featured some powerful first serves.

Serena did not have her best serving day overall, placing just 53 percent of her first serves into play, but she benefited from 32 unforced errors by Giorgi.

Stephens Falls

Sloane Stephens entered the Australian Open on an uptick after her title in Auckland. There, she played aggressive and confident tennis. But that was not the case in her opening round match against qualifier Qiang Wang, who would upset the American 6-3 6-3.

It was a match where Stephens did not appear as focused mentally and often showed poor footwork on her groundstrokes. And Wang, who struck surprisingly aggressive shots, took full advantage of it.

It was a disappointing result for the world No. 26, who came into Melbourne with such optimism. But 36 unforced errors would do her in. Meanwhile, the world No. 101 will move on to face Anna-Lena Friedsam in the second round.

Djokovic Rolls

It took several games to find his rhythm, but top-seeded Novak Djokovic picked up where he left off at the U. S. Open, rolling against Hyeon Chung, 6-3 6-2 6-4.

The young Korean showed potential by going neck and neck early with the world No. 1, battling nicely from the baseline and breaking serve. But while Djokovic was not in his top form, he worked his way back into a groove and appeared to wear down Chung as the youngster may have struggled with the heat.

Despite wearing down, the 19-year-old showed glimpses of some impressive shot-making. But the 10-time major champion appears to be the player to beat once again early in the tournament. He advanced to the second round behind 40 winners.

Nishikori Impressive

On paper, it appeared seventh-seeded Kei Nishikori was in for a challenge in his first-round match against Philipp Kohlschreiber. After all, the German has a reputation of being a tough out in Grand Slam matches, particularly on the hard courts. But on Monday, he was no match for Nishikori, who cruised 6-4 6-3 6-3.

Nishikori’s game was in question entering Melbourne, due to the fact that he only had one successful result under his belt before he fell to Bernard Tomic in Brisbane. But the Japan native served well and controlled the tempo during the match. It was an efficient, workmanlike effort as Nishikori would break the Kohlschreiber serve four times while protecting his own serve throughout the match.

The 26-year-old, who always has a strong following in Australia, has a favorable route to the round of 16, where he could face Jo-Wilfred Tsonga if the favorites advance.