Serena motors into fourth round in Melbourne

MELBOURNE (Reuters) - Serena Williams powered into the fourth round of the Australian Open on Saturday with a 6-2 6-1 demolition of Ukrainian teenager Dayana Yastremska to continue her charge through the Melbourne Park draw. The 37-year-old Williams, chasing a record-extending eighth Melbourne title in the professional era, barely broke sweat on a sunny afternoon at Rod Laver Arena as she sent 20 winners flying past the 57th-ranked 18-year-old. Yastremska rolled her right ankle midway through and took a medical time-out to have her foot bandaged when trailing 4-1 in the second set. It stalled defeat only briefly, however, as Williams broke her a third time in the set and claimed the match when the Ukrainian sprayed a cross-court forehand wide. Williams will play the winner of the match between her older sister Venus and top seed Simona Halep for a place in the quarter-finals.