MIAMI • Swiss tennis star Roger Federer's impressive return from injury has prompted talk of his possible return to No. 1 in the world, but the 18-time Grand Slam winner says looking after his body is far more important than chasing the rankings positions.
Since coming back from a six month injury layoff, the 35-year- old has won the Australian Open and Indian Wells this year and on Monday, cruised past Juan Martin del Potro 6-3, 6-4 to move into the fourth round of the Miami Open.
On the eve of the tournament, his compatriot Stan Wawrinka said he believed Federer, ranked sixth, could get back to No. 1 in the world, but Federer said he had other things on his mind.
"It's not the priority. Health needs to be the priority. That's why if I were to get there again I have to really win a lot of big tournaments, and I know how hard that is. I tried to do it for the last five years," he said.
"For me, the priority is actually to win tournaments at this point in my career. The rankings is very secondary."
On Monday, Federer was forced to save four break points in the first set but he got ahead with a thundering forehand to take a 5-3 lead and served out for the set.
Del Potro had a chance to turn things around when he had a break point when down 4-3 in the second set but Federer, moving well and looking full of confidence, held firm and wrapped up the match in one hour and 22 minutes.
"I felt like I was in control and I was able to generate more chances than he did," Federer said.
"I feel like I earned it more. I was more the aggressor. It was more on my racket, and I like it that way."
Federer will face 14th-seeded Spaniard Roberto Bautista Agut in the next round.
Wawrinka, who defeated Tunisian Malek Jaziri 6-3, 6-4, will come up against Alexander Zverev of Germany in the fourth round.
Zverev pulled off a remarkable win over American John Isner, saving three match points as he came back from a set down to triumph 6-7 (5-7), 7-6 (9-7), 7-6 (7-5).
In the women's tournament, world No. 1 Angelique Kerber despatched Japanese qualifier Risa Ozaki 6-2, 6-2 to set up a quarter-final clash with Venus Williams.
Seven-time Grand Slam champion Williams beat Russian seventh-seed Svetlana Kuznetsova 6-3, 7-6 (7-4).
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