3-time champ Serena Williams into US Open's 4th round

Serena Williams reeled off the last eight games and reached the U.S. Open's fourth round with a 6-4, 6-0 victory Saturday over 42nd-ranked Ekaterina Makarova of Russia, who upset the American at the Australian Open in January.

The fourth-seeded Williams hit eight aces and won 32 of the 40 points she served.

The match was even at 4-all in the first set, when Williams broke the left-handed Makarova for the first time to seize control in Arthur Ashe Stadium.

Williams' fourth-round loss to Makarova in Melbourne is the only defeat in 22 Grand Slam matches against lefties for the 14-time major champion.

This time, though, Williams built a 31-10 edge in winners and moved a step closer to a fourth U.S. Open title.