Serena Williams has booked her place in the quarter-finals of the Italian Open by beating Christina McHale in straight sets.
The world number one, competing in her first tournament since March, progressed through with a 7-6(7) 6-1 victory in Rome.
A loss of serve in the fifth game left Williams on the back foot, but she quickly recovered to earn a break of her own to force a tie-break.
Having wasted two set points, the American finally edged out her stubborn opponent to open the way for a more straightforward second set.
McHale lost serve three times in a set lasting 30 minutes, which allowed her compatriot to wrap things up and set up a meeting with Svetlana Kuznetsova in the last eight.
