overcoming italy 's sara errani 4-6 , 7-6 -lrb- 3 -rrb- , 6-3 in a fed cup play-off sunday .
while williams held a massive 70-7 lead in winners , she committed nearly three times as many unforced errors as the 15th-ranked errani .
still , williams improved to 20-0 this year and 16-0 in fed cup for her career .
next up , brindisi-born flavia pennetta was facing 65th-ranked christina mchale , followed by a potentially decisive doubles match .
but the wind prevented her from stepping too far into the court .