(30-5), the No. 7 seed, moved on to the second round on Saturday at the Ford Center.
Northern Iowa (29-4), the Missouri Valley Conference champion and the No. 9 seed, moved on to the Round of 16.
Nadal was winning so comfortably that the atmosphere was completely flat, and the top seed moved further ahead with another break for 5-2.
The No 30 seed moved into the third round of the US Open here with her second convincing victory of the week, beating France's Caroline Garcia 6-4, 7-6.
Williams' scheduled fourth-round opponent is Vera Zvonareva and the seventh seed moved a step closer to that clash with a 6-1 7-6 (7/3) victoverover Lucie Hradecka.
The Smiths had just watched Murray, the fourth seed, move a step closer to a possible semifinal match against the defending men's champion, Rafael Nadal, with a 6-3, 6-3, 7-5 victory against Tobias Kamke, who managed a single break point — which he failed to convert — in the 1-hour-57-minute second-round match.
Lopez's compatriot David Ferrer, the seventh seed, moved into the third round after beating American Ryan Harrison 6-7 (6-8) 6-1 4-6 6-3 6-2 in a match suspended from Thursday evening.
The top seed moved 5-2 clear thanks to some typically athletic defence and a deep return, and closed out the set after 29 minutes.
A day after two No. 15 seeds made history and advanced to the next round -- something that previously happened just four other times in the history of the NCAA Tournament -- every high seed moved on to the Sweet 16.
(12) In view of the expiry of the 'Derogatory experiment on seed sampling and seed analysis' set out in Annex V(A) to the Decision adopted by the Council of the Organisation for Economic Co-operation and DevelOECDnt (onCD) on 28 September 2000 on the OECD Schemes for the Varietal Certification of Seed Moving in International Trade, any reference to that experiment should be deleted.
