Unconvincing Agnieszka Radwanska sees off Jelena Jankovic

Agnieszka Radwanska has booked her place in the fourth round of the US Open, overcoming Jelena Jankovic in straight sets at Flushing Meadows.

The second seed broke early but then dropped serve herself before breaking Jankovic again.

Serbian Jankovic then failed to convert three break points as Radwanska took an unpredictable opening set 6-3.

There was even less consistency in the second as both players dropped serve a further seven times between them, but the Pole eventually came out on top 7-5 to progress.