Roger Federer races through at Indian Wells

Second seed has no problems against Ivan Dodig

Roger Federer in action at Indian Wells (GETTY IMAGES)

Second seed Roger Federer was caused few problems by Ivan Dodig as he raced into the fourth round of the BNP Paribas Open in Indian Wells - but there was a minor scare in the form of some back pain.

Dodig started out well, but once his illustrious opponent had broken there was little fight from the Croatian, ranked 60th in the world, and Federer sprinted to a 6-3 6-1 win in 61 minutes, with a back twinge in the penultimate game doing nothing to slow him down.

"I'm happy with the way im playing," Federer, who had never previously played Dodig, told Sky Sports 2. "I found my way at the end of the first. The beginning of the second I started to play better."

Dodig immediately brought up three break points in the first game of the match, but former world number one Federer won five points in a row to hold.

The set went with serve until game eight, when Dodig handed Federer a set point with a double fault, then threw in a second to surrender the game.

Dodig saved three set points, the first with an exquisite backhand drop shot, but it was fourth time lucky for Federer when his opponent sent a return wide.

That seemed to break the resistance of the Croatian, and Federer broke to open up the second set, then again in game three for a 3-0 lead.

Dodig finally held to get on the board at 4-1, but it was the tiniest flicker of resistance as, in the Croatian's next service game, Federer brought up two match points and another double fault proved decisive.

The only worry for Federer was a slight twinge in his back near the end of the match.

"I felt a little something in my back at the end," he said. "I'll just have to check it out and hopefully I'll be fine for the next match."

Next up for Federer is an all-Swiss clash with his friend and Davis Cup team-mate Stanislas Wawrinka, who overcame a battling Lleyton Hewitt 6-4 7-5.

Wawrinka broke through in game five when he showed good touch at the net, then kept control on his serve to leave Hewitt serving to stay in the set at 5-3.

The Australian held, then forced three break points in the next game, but Wawrinka won five points in a row - with the help of a HawkEye overrule which left Hewitt furious - and took the set 6-4.

The pair traded breaks in the second, but Hewitt could not match his opponent's big shots and the Swiss broke again to take the match.

Fifth seed Rafael Nadal did not have to even take to the court as he reached the fourth round courtesy of a walkover after Argentinian opponent Leonardo Mayer withdrew with a back injury.

Nadal will face Ernests Gulbis after the Latvian qualifier beat 20th seed Andreas Seppi 5-7 6-3 6-4 in two hours eight minutes.

Gulbis roared into a 4-0 and 5-2 lead but allowed Seppi to get back into the match to win the first set 7-5.

Such was his frustration that Gulbis was given a warning by the umpire, breaking his racket and also flicking out at the umpire's chair with his towel, but he composed himself to claim a notable win.

Sixth seed Tomas Berdych served notice of his intention as he enjoyed an ultimately authoritative 6-4 6-1 win over 27th seed Florian Mayer, while South African Kevin Anderson dominated on serve as he beat Jarkko Nieminen 6-1 6-1 in exactly an hour.

There were also wins for 13th seed Gilles Simon, 3-6 7-6 (7/5) 6-4 in his all-French encounter with Benoit Paire, and 10th-seeded compatriot Richard Gasquet, 6-1 6-4 over Poland's Jerzy Janowicz.

In the women's tournament, there was an upset as 2008 champion Ana Ivanovic, seeded 11th this year, was beaten in three sets by Mona Barthel of Germany.

The Serb seemed to have found her touch in the second set but was overwhelmed by the 24th seed as she fell to a 6-1 3-6 6-0 defeat.

Top seed and defending champion Victoria Azarenka overcame a first-set blip to sweep past Belgium's Kirsten Flipkens 3-6 6-3 6-0.

Former world number one Caroline Wozniacki eased to a 6-2 6-1 win over Elena Vesnina.

Wozniacki, enjoying better form these days, took the first set in little more than 40 minutes after being far more effective on her serve.

Wozniacki, the seventh seed, broke at the start of the second set and moved into a 3-0 lead and her opponent could only take one game before going down in one hour 15 minutes.

Seventh seed Sam Stosur beat Peng Shuai 6-3 3-6 6-2 in two hours and 12 minutes.

Both players struggled for consistency on serve but it was Stosur who prevailed.

Elsewhere, there were straight-sets wins for fourth seed Angelique Kerber, Urszula Radwanska, Nadia Petrova and Garbine Muguruza.

PA