US Open Tennis Day 5

NEW YORK – There isn't a ton of home-country content left in this U.S. Open – no offense to the friends and family of Tim Smyczek.

In the absence of the stars and stripes, he usually fills in just fine as a pseudo-local favorite.

Meanwhile, the women are starting the third round, which means the seeds will begin to square off.

Federer has a night match on Arthur Ashe Stadium against Australian Sam Groth and his massive serve, which will be followed by a women's match full of firepower involving Maria Sharapova and Sabine Lisicki.

Federer, generally speaking, doesn't have much trouble with big serves. As proof, we offer his last two matches against huge-serving Canadian Milos Raonic, at WImbledon and a few weeks ago in Cincinnati.

MATCHES TO WATCH - MEN

[11] Ernests Gulbis (LAT) vs Dominic Thiem (AUT)

There are a lot of subplots weaving through this appealing second-round matchup, starting with the fact that the mercurial, brilliantly-talented Gulbis and the 20-year-old with the sweet one-handed backhand, Thiem, share a coach, a training base, and a clothing sponsor. The notion that the flaky 25-year-old Latvian, whose press conferences are always highly entertaining and well-attended (as are his matches) can serve as a sort of mentor to Thiem, who looks like someone's eager little brother but who has a very grown-up game, is a fascinating one. And it's always absorbing to watch a contest between two players who know each other well and are good friends.

Gulbis has been ripping it up in practice and, if he's focused and on his game, can beat any of the players remaining in the tournament. Yes, any of them. The questions that are asked every time he takes the court are about whether he will be 1) focused and 2) on his game. The two have met only once, back when Thiem was just 18.

Venus and Serena Williams, who had a tough one against No. 7 seeds Kristina Mladenovic and Timea Babos in the first round of doubles, should have an easier time today against Oksana Kalashnikova

The junior qualifying gets under way today, and there will be plenty of young American kids trying to get into the U.S. Open junior main draw. You have to leave the site to see them, though; they'll be competing on auxiliary practice courts just outside the gates.