Nadal, Federer win again in straight sets 2-ranked Rafael Nadal picked up his fourth straight-set victory of the 2012 Australian Open with a win Sunday over Feliciano Lopez. Nadal lost serve just once in a 6-4, 6-4, 6-2 decision over Lopez. The match was relatively lengthy for Nadal -- 2 hours, 45 minutes -- but Nadal still took 58 percent of the points, including 77 percent on serve. He also won nearly half (50-of-109) of the points when receiving and finished off five of his 18 break-point chances versus Lopez, who was the No. 18 seed. Seventh-seeded Tomas Berdych earned a quarterfinal shot at Nadal with a taut 4-6, 7-6 (7-5), 7-6 (7-3), 7-6 (7-2) win against 10th-seeded Nicolas Almagro. Berdych managed just one break in the nearly 4-hour match but survived with the advantage in the tiebreakers. Roger Federer, seeded third, took out unseeded Australian Bernard Tomic 6-4, 6-2, 6-2 with six service breaks. Tomic landed 75 percent of his first serves but Federer still won 48 percent of the points off Tomic's serve. Tomic's loss leaves Lleyton Hewitt, who plays world No. 1 and defending champion Novak Djokovic in the fourth round Monday, as the last Australian in the field. 11-seeded Juan Martin del Potro ran past Philipp Kohlschreiber 6-4, 6-2, 6-1 with at least two breaks in each set. Federer owns a 7-2 series edge over del Potro going into their quarterfinal match. One of del Potro's wins over Federer was a five-set victory in the finals of the 2009 U.S. Open. Nadal is 10-3 versus Berdych, including taking the last nine meetings.