Rain: As the weather for tennis turns foul, the players will begin to stew this week. They'll lose some days off, too, and that will add to the pressure. This will mainly benefit the underdogs. One particular case worth watching will be Federer/Nalbandian -- scheduled for today, but unlikely to go ahead soon. Federer's match against James Blake was two sets of classic Federer perfection bracketing an awful middle set of missed breaks, lost focus, and surprising errors. Federer took the set anyway, but any boxing judge would've given it to Blake; he looked more in control than Federer. Nalbandian won't be as forgiving. This could be a classic match, with the winner likely to meet Roddick.

Federer needs to head to the net more against the Argentinian; he traded groundstrokes nicely with Blake, but Nalbandian has more variety and more consistency. Federer will have to look for volley opportunities to put the points away early. And if he has mid-set lapses like he had in the third round, Nalbandian will eat his lunch.

Other underdogs are in contention. Paradorn Srichiphan is likely hoping for rain interruptions to help rattle Hewitt, who has rattled quite easily this year. It's not as long a shot as it appears. I think Scrichiphan can ride into the quarters by testing Hewitt's confidence, like a pitcher might brush back an aggressive hitter. And Todd Martin has a good shot for the quarters against Juan Carlos Ferrero, but only if he makes use of every opportunity to remind Ferrero that these are hard courts by putting heat on the serve and stepping into the volley, which should help him pick up a half-second on the quick Spaniard, who is a decade younger than Greybeard Todd. Martin has a long reach and should cover the net well. Hell, I'm feeling foolish. Put me down for both Martin and Srichiphan, and lightning on the deuce points.