Indian Wells, CA (SportsNetwork.com) - Defending champion Rafael Nadal survived an upset scare from Radek Stepanek to move on in second-round play at the $4.72 million BNP Paribas Open, the first Masters 1000 event of the year.

The top-seeded Nadal, who topped Juan Martin del Potro in last year's marquee finale, dropped the first set and trailed deep in the third against the 35- year-old Stepanek before ultimately rallying for a 2-6, 6-4, 7-5 victory.

Stanislas Wawrinka had an easier time in his Saturday match, as the third- seeded Australian Open champ handled Ivo Karlovic by a 6-3, 7-5 score.

Fifth-seeded Andy Murray was also pushed to a third set by Lukas Rosol, but the 2009 Indian Wells runner-up still came through with a 4-6, 6-3, 6-2 win.

Murray lost to Nadal, who also titled here in 2007, in the 2009 final.

Also, four-time Indian Wells champion Roger Federer, seeded seventh in this event, advanced via a 6-2, 7-6 (7-5) verdict over Paul-Henri Mathieu.

Other seeded winners on Saturday included No. 10 Milos Raonic, who outlasted Edouard Roger-Vasselin 7-6 (7-4), 4-6, 7-6 (7-2). Eleventh-seeded Tommy Haas downed Jeremy Chardy 6-3, 6-4; No. 13 Fabio Fognini took out American Ryan Harrison 5-7, 6-1, 6-4 and 17th-seeded Kevin Anderson bested veteran Lleyton Hewitt 7-6 (7-5), 6-4.

No. 18 seed Jerzy Janowicz was ousted in his second-round bout by Alejandro Falla, who won a third-set tiebreaker to prevail 6-3, 2-6, 7-6 (7-5). Pablo Andujar, seeded 32nd, also fell, with Jiri Veseley taking a 6-1, 2-6, 6-1 win over the Spaniard.

In other results, ninteenth-seeded Kei Nishikori (19) rolled to a 6-1, 6-3 triumph over Santiago Giraldo; No. 23 seed Gael Monfils dusted Sergiy Stakhovsky by a 6-2, 6-4 count; No. 27 Dmitry Tursunov (27) downed Juan Monaco 7-6 (7-4), 6-4; No. 28 Alexandr Dolgopolov got past Tim Smyczek 7-6 (7-3), 6-4; 29th-seeded Andreas Seppi bested American Sam Querrey 4-6, 7-6 (7-3), 6-3 and Evgeny Donskoy posted a 6-4, 6-3 win over Michael Russell.