Serena Williams won the battle of the ages against Dayana Yastremska as the former world number one booked a last-16 berth at the Australian Open.

Almost 20 years separated 37-year-old Williams and 18-year-old Yastremska, who was not even born when the American great won the first of her 23 grand slam titles at the 1999 US Open.

And Williams' experience was telling as she overpowered the Ukrainian teenager - featuring in just her second slam main draw - 6-2 6-1 on Rod Laver Arena in Melbourne on Saturday.

After posting her 10th successive victory without dropping a set at the Australian Open, Williams could face either top seed Simona Halep or sister Venus Williams in the round of 16.

Yastremska, who became the first 2000s-born player to break into the WTA's top 100 last season, looked nervous from the outset, double-faulting twice in the opening game to hand the break straight to seven-time Australian Open champion Williams.

Serving at just 29 per cent did not help but there were flashes of Yastremska's potential and even when she appeared to have done enough to win a point with a well-executed drop shot, Williams stepped up by hitting a stunning winner down the line.

Williams - seeking a record-equalling 24th slam crown - was composed throughout under the Melbourne sun, while Yastremska was overcome with emotion as she fell behind a break in the second set.

And there was only one result from that point, 16th seed Williams sailing through to keep her quest for an eighth Daphne Akhurst Memorial Cup alive.

STATISTICAL BREAKDOWN
S Williams [16] bt Yastremska 6-2 6-1

WINNERS/UNFORCED ERRORS
Williams - 20/13
Yastremska - 14/26

ACES/DOUBLE FAULTS
Williams - 8/1
Yastremska - 2/8

BREAK POINTS WON
Williams - 5/12
Yastremska - 0/0

FIRST SERVE PERCENTAGE
Williams - 68
Yastremska - 43

PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE
Williams - 85/50
Yastremska - 62/35

TOTAL POINTS
Williams - 60
Yastremska - 38