Chile at U.S.

What remains to be seen is how the Chileans adapt to the Mission Hills lawns, which through the one-week run-up to the event have been playing rather hardcourt-like.

The U.S. opted for grass after some heavy lobbying from Roddick, and the two-time Wimbledon runner-up could use the boost after his struggling season thus far. Blake, who at the No. 2 singles spot has the hotter hand than Roddick this year, has ironically struggled on grass, in 2005 failing to reach the quarters at Queen's then losing first round at Wimbledon. Blake missed Wimbledon in 2004, and in 2003 was 1-2 on grass.

"It feels great to me," said Blake of his practice on the lawns earlier this week. "I think any time getting on a grasscourt is going to be pretty fast, especially a lot faster than the hardcourts we've been hitting on. Feels good. It's just going to be a matter of time getting used to it."

It's apparently not a huge adjustment for the Chileans either.

"I'm happy for them that they're comfortable, and I think we're pretty comfortable as well on the grass." Blake said. "Especially, Andy, he's always very comfortable when he's playing on grass."

The Bryan brothers say their doubles against the reigning Olympic doubles champions is anything but a "gimme."

"They both have great first serves," said Bob Bryan. "Gonzalez has a huge forehand. Massu is really solid on both sides. They both fight really hard. Hopefully, we can expose some of their net play out on the doubles court. I know they like to stay on the baseline."

Last year Gonzalez beat big-serving Roddick clone Joachim Johansson en route to the quarterfinals at Wimbledon, while Massu lost second round at Wimbledon, his only grasscourt event of the year.

"We will try to do our best," Massu said. "We don't have anything to lose. The USA have to win the tie."

Match-ups for Friday kicking off the tie will be Blake vs. Gonzalez, then Roddick vs. Massu.