All the action as top seed Serena Williams secures a straight sets victory over Belgium's Els Callens in Melbourne.

---

Game-by-game updates:

Second set

S Williams 6-4 6-0 Callens
Williams goes a break point down at 30-40 and Callens saves a first match point with a superb forehand. But Serena recovers her composure to take victory in a little under an hour.

S Williams 6-4 5-0 Callens
Callens is now struggling to win points on her own serve as Serena breaks for the third time in the set to move within a game of victory.

S Williams 6-4 4-0 Callens
A third ace from Williams gets her back to 30-all and a ferocious backhand points her towards another successful service game.

S Williams 6-4 3-0 Callens
The wheels are coming off Callens' challenge as a first double fault and a netted backhand see her drop her serve to love.

S Williams 6-4 2-0 Callens
A straightforward service game from the number one seed to cement her command of the match.

S Williams 6-4 1-0 Callens
Callens remains competitive in the rallies but Serena breaks the Belgian's serve in the opening game to put herself on course for victory.

---

First set

S Williams 6-4 Callens
Serena's first ace of the match gives her two set points. She misses the first but another ace gives her the opening set.

S Williams 5-4 Callens
Callens stays alive in the set with a superb service game to love featuring some precise volleying.

S Williams 5-3 Callens
Callens tries to advance to the net but Williams is too powerful from the baseline as she moves to within a game of taking the first set.

S Williams 4-3 Callens
Callens is undaunted and rediscovers the aggression of her early games to stay in the set with a solid service game.

S Williams 4-2 Callens
Callens manages to stay with Williams in some long rallies but the number one seed holds to 30 to take command of the match.

S Williams 3-2 Callens
Williams moves up a gear with some powerful forehands to earn three break points, and takes the second of them when Callas nets a forehand.

S Williams 2-2 Callens
Callens tries to attack every shot but this time is unable to make any headway as Serena holds serve to love.

S Williams 1-2 Callens
Williams continues to look rusty despite one fierce cross-court forehand return, Callens holding to 15 with some fine serving and volleying.

S Williams 1-1 Callens
Callens earns one break point with a precise overhead and another at deuce, but overhits a backhand and Serena recovers to draw level.

S Williams 0-1 Callens
Williams wins two points on the Callens serve, but the Belgian holds impressively in a promising start.