Before each day's play Down Under, TENNIS.com editor Ed McGrogan will pick his three must-see matches.

David Nalbandian [27] vs. Lleyton Hewitt (Rod Laver Arena, second night match)
—Hewitt leads head-to-head 3-2

It will be turn back the clock night at Rod Laver Arena when these 29-year-old former greats collide. They’ve met here once before, in the 2005 quarterfinals—Hewitt held off Nalbandian in a 6-3, 6-2, 1-6, 3-6, 10-8 classic. Another five-setter would officially get this year’s tournament into gear, but both men would have to be playing well—or, ironically, both not be playing well—for that to happen. Hewitt’s win at the Kooyong warm-up should give him some confidence, and his overall consistency, coupled with the crowd support, should see him through past the erratic Argentine.

The pick: Hewitt in four sets.

Donald Young vs. Marin Cilic (Court 2, second match)
—First career meeting

Young has already had a successful Australian Open, having won three qualifying matches to reach the main draw. But this is a good litmus test to see if he’s actually turned his game around for the new year. He could have drawn a lower-seeded opponent, but Cilic is also a bit of a mystery. After a strong start to 2010 which included a semifinal run here, Cilic faded, and he lost his only tour match this season to Kei Nishikori. Only the most patriotic supporters could back Young here, but I could see him snagging a set. U.S. viewers should get a close look at this contest on ESPN2.

The pick: Cilic in four sets.

Martina Jose Martinez Sanchez [26] vs. Greta Arn (Court 19, third match)

Arn was impressive earlier this month in Auckland, defeating four seeded players, including Maria Sharapova and Yanina Wickmayer, to win her second WTA title. Based on those scalps, it would appear that the 31-year-old shouldn’t have much trouble with Martinez Sanchez. But the Spaniard is a tricky opponent, employing an array of shots and crafty approaches that most of her peers wouldn’t dare try. Still, she doesn’t hit a big ball, which could be her downfall. If Arn can hit through the court, she’ll move on through to the second round.

The pick: Arn in three sets.

Honorable Mention: Ernests Gulbis [24] vs. Benjamin Becker (Court 18, third match)
—First career meeting

Some serious wattage in this one; the ball changes can't come soon enough.

The pick: Becker in five sets.