BNP Paribas Open: Rafa Nadal won his opening match against Ryan Harrison

BNP Paribas Open: Rafa Nadal won his opening match against Ryan Harrison

Seeded fifth for the Masters Series event, the Spaniard overcame the American 7-6 6-2 in his first hardcourt match in almost a year.

Nadal moved into a 4-1 lead early on but a couple of ill-timed double faults and some wayward forehands allowed Harrison to level.

The two-time champion saved a break point to lead 6-5 but took charge of the tie-breaker and closed out the set.

Once again he went up early in the second set and this time there was no comeback from Harrison, Nadal serving out to love.

"Any victory is important for me because that gives me the chance to play another day," said Nadal, who is on the comeback trail after missing seven months with a knee injury.

"That's what I need, to play matches. I need to compete."

Nadal is on course to face Roger Federer in the quarter-finals after the Swiss won his match against Denis Istomin 6-2 6-3.

The second seed was in ruthless form as he despatched the Uzbek in 57 minutes without facing a single break point.

Fourth-seed David Ferrer, who has overtaken Nadal in the world rankings, was the first major casualty after being beaten 3-6 6-4 6-3 by 37th-ranked South African Kevin Anderson.

The defeat followed Ferrer's comprehensive 6-0 6-2 loss to Nadal in the final at Acapulco last week.

France's Gilles Simon saved three match points in a 6-3 3-6 7-5 victory over Paolo Lorenzi, while Australian veteran Lleyton Hewitt beat last year's runner-up John Isner 6-7 6-3 6-4.

And in the final match of the day Tomas Berdych, seeded sixth, beat Mischa Zverev 6-2 6-4.