Roger Federer through in Cincinnati, Serena Williams also progresses

Federer comfortably beat Del Potro, who beat him in the 2009 US Open final

Roger Federer eased through to the third round of the Western & Southern Open with a comfortable victory over Juan Martin del Potro.

The world number three lost to the Argentine in the 2009 US Open final, but there was little danger of a repeat in Ohio as Federer won 6-3 7-5.
In the women's event, Maria Sharapova safely progressed into round three with a 6-1 6-3 win over Anastasia Rodionova.
Britain's Andy Murray plays his opener against David Nalbandian on Wednesday.
Sharapova easily beat Rodionova Federer looked at his comfortable best during the first set against Del Potro, but the Argentine fought back in a much more competitive second set which went with serve until the Swiss broke to go 6-5 up.
America's James Blake will meet Federer in the third round at the Western & Southern Open after beating Italy's Fabio Fognini 6-4 6-2.
The other man through to round three is Tomas Berdych. The Czech beat Juan Monaco from Argentina 7-6 (7-2) 6-0, winning 83% of points on first-serve.
In the first round, Wimbledon semi-finalist Jo-Wilfried Tsonga seemed to have recovered fully from an arm injury which forced him to retire during his Montreal Masters semi-final against Novak Djokovic last week.
The Frenchman defeated Croatia's Marin Cilic 6-3 6-4, dropping only six points on serve and hitting nine aces.
"I didn't play the last two days because of my arm, and this morning at the warm-up I was feeling really good. It was a really fluid match. Everything was easy for me today, including my serve," Tsonga said.
Serena Williams held off a late fightback from Lucie Hradecka to win her first-round match and continue her excellent run of form.
The American, who made it back-to-back tournament wins when she won the Rogers Cup last Sunday, battled to a 6-3 7-6 (7-5) win in one hour 39 minutes.
The 13-time Grand Slam champion is currently ranked 31 in the world as she continues her comeback from injury and illness.
Unseeded Williams flew through the first set, winning 89% of her first serve points and breaking the Czech once to take the set 6-3.
That form continued in the second set as the American went a double break up to serve for the set at 5-2.
But Hradecka rallied and broke back twice to level the set before forcing a tie-break.
With the score level at 5-5 in the tie-break, Williams secured the mini-break before serving out to set up a repeat of Sunday's Rogers Cup final against Samantha Stosur.
Petra Kvitova, Li Na and Marion Bartoli also recorded victories to join Sharapova in round three.