Top seed Andy Roddick and number three Andy Murray moved closer to another semi-final showdown by easing into the Memphis International quarters on Thursday.
Roddick saw off German Benjamin Becker 7-6, 6-4 and Murray, who beat the American on his way to the San Jose title last weekend, battled past Dane Kristian Pless 6-3, 7-6.
Defending champion Tommy Haas and Mardy Fish also won as the top four seeds made it through to the quarter-finals.
Roddick hit 14 aces to beat Becker, the world number 45 who is best known for sending former world number one Andre Agassi into retirement at last year's US Open.
Top seed Roddick, who also beat Becker at Flushing Meadows last year, took the first-set tiebreak 7-4 and one service break, in the third game of the second set, was enough to put him through to a clash with Yen-Hsun Lu of Taipei.
"I thought I outplayed him from the baseline today," Roddick told reporters. "And I started hitting my forehand much better.
"I hit it great in the Czech Republic (in Davis Cup) and then last week I don't know if I could have hit a forehand into the sea from the beach. But I feel much better about my game now."
Lu advanced when Austrian Juergen Melzer retired trailing 7-6, 1-1 because of a stomach illness that has affected several players in the tournament.
Third seed Murray faced just one break point against Pless.
After breaking serve once to win the first set, he played a good tiebreak in the second to win it 7-4 and set up a quarter-final against Austrian Stefan Koubek.
"I thought I hit the ball much better today," Murray said, after beating Pless at the same stage for the second successive week.
"I didn't serve that consistently but when my first serve went in I won 90 percent of the points."
SEVEN STRAIGHT
Murray was beaten in the quarter-finals in Memphis last year, ending a run of seven straight wins that began when he won in San Jose.
"I'd like to go one better (than seven) and put myself in a position where I have a chance of winning the tournament," he said.
"Maybe I need to play a little more aggressively on break points. I've been putting the return in play but not really following it up."
Haas, the winner in 1999 and 2006, needed two tiebreaks to get the better of American Amer Delic.
In a match that did not contain a single break point, the German clinched victory in one hour, 27 minutes and will now play American wildcard Sam Querrey, who upset French seventh seed Julien Benneteau 6-3, 6-4.
"I think we both served well today and it was very close," second seed Haas said.
"It really just came down to a couple of tiebreaks and I just won a couple of points there. He almost came back in the second one, but it was a good win."
Fourth seed Fish slammed 22 aces on his way to a 6-1, 7-6 win over Argentine Juan Martin del Potro.
The American saved two set points before winning the tiebreak 11-9 to set up a quarter-final clash with Russian qualifier Teimuraz Gabashvili.
