Good evening, all, and welcome to our LIVE coverage of Serena Williams v Vania King in the second round of the US Open.

Williams 6-3 6-3 King: Break on the second match point for Serena Williams, who goes to the net shaking her head, obviously disappointed with her own performance. Still, reasonably straightforward day at the office for her.

Williams 6-3 5-3 King: Williams is almost there now, and the umpire continues to hush the crowd.

Williams 6-3 4-3 King: Vania King is staying with Williams all the way now, but were those early errors just too much for her to overcome?

Williams 6-3 4-2 King: Williams is looking tense as she moves within touching distance of the third round. She's not seemed comfortable at all today.

Williams 6-3 3-2 King: King's forehand is still looking excellent and putting Williams under pressure.

Williams 6-3 2-1 King: Another holler from Williams as she breaks, and then again it's quickly back to her chair to towel down.

Williams 6-3 1-1 King: Serena shakes her head at herself, allowing her advantage to slip to deuce, and then delivers an ace at 121mph. She's playing some erratic tennis.

Williams 6-3 0-1 King: Vania King's knee is heavily taped and Williams is cranking up the power, letting rip with a roar as she returns with menace. But King is tenacious and she's forcing Williams into errors as she holds.

Williams 6-3 King: Vania King threatens to break the Williams serve, at least a touch, with the world number one looking a bit wobbly on her forehand. Still, she comes through to take a first set that's transpired to be much more competitive than might have initially been expected.

Williams 5-3 King: King is coming to the net a bit more now, and leaving Serena stranded. If the opening games were the result of nerves, she's settling into her serve.

In case you're interested in star-spotting, Beyonce and Jay-Z are in the crowd.

Williams 5-2 King: Williams holds her serve and is quick to her chair and her cold towel.

Williams 4-2 King: Williams applauds Vania King's determination and some brilliant shot-making. She also sighs heavily when resuming her place on the baseline - whether through frustration or exhaustion, that's not quite clear.

Williams 4-1 King: Still quiet on Ashe as Serena continues to do Serena things. She's not playing particularly well against her compatriot but she's doing enough.

Williams 3-1 King: King is putting some heft behind that forehand but she's struggling to manage the length. Still, Serena's not quite at Serena levels today, and she has a fistful of break points she doesn't convert.

Williams 3-0 King: Williams's serve isn't impregnable this evening so far, but it still has more than King can currently muster.

Williams 2-0 King: Wow, Serena is stalking King like prey, forcing her round the court and taking her serve apart.

Williams 1-0 King: Serena is shaky on her serve from the start but pulls herself together to dish up a couple of aces and take the game.