MELBOURNE, Australia -- Here's a look at a few notable matches on Day 7 of the Australian Open:
Novak Djokovic (3) vs. Marcos Baghdatis: If the crowd behaves, this one should be a whole lot of fun. In one corner lies Djokovic, the defending champion backed by loud, passionate Serbs. In the other is showman Baghdatis, cheered by hoards of no less fervent Greeks and Cypriots.
Djokovic is desperately hoping to regain the form he exhibited in early 2008, while Baghdatis is trying to resurrect a career that blossomed when he unexpectedly, and delightfully, made the final here three years ago. Up a set and a break -- almost a double break -- Baghdatis nearly pulled off one of the biggest tournament upsets of all time against Roger Federer in the finale. Surprise, surprise, the Fed Express derailed Baghdatis in four.
Since then, Baghdatis has dumped about as many coaches as French pal Gael Monfils has. Baghdatis has also been dogged by injury and lack of intensity, and his progression ceased. Entering the Australian Open, the 23-year-old's ranking sat precariously at 97th. Perhaps wanting a new start, he departed with his trademark locks, going for the shaved look instead. His girlfriend apparently didn't like the new look.
Djokovic can't like his own performance so far. Calling himself one of the favorites along with Federer and world No. 1 Rafael Nadal -- he purposefully neglected Andy Murray -- Djokovic hasn't fit the bill. There was a first-round blip against unknown Italian Andrea Stoppini and another setback against Bosnian-born Amer Delic, a lucky loser ranked outside the top 100. Delic stretched Djokovic to four sets Friday and blew two set points to take the affair into a fifth. Who knows what might have happened then?
Tweaking his service motion in an effort to get more pop and using a new racket haven't helped.
"I can't play perfect tennis," Djokovic said following his encounter with Delic. "It's normal to have ups and downs during the tournament and during the matches. I've played, I think, the best tournament of my life here last year, which helps me out for this year."
Baghdatis, like everyone else, labored in the intense heat Monday, yet still eliminated awkward Frenchman Julien Benneteau in straight sets. Down and out against hard-hitting Robin Soderling -- trailing by a set and 4-0 in the second -- Baghdatis awoke and triumphed in four.
The previous meeting between Baghdatis and Djokovic was highly memorable. Djokovic emerged 7-6 (4), 7-6 (9), 6-7 (3), 4-6, 7-5 in a 5-hour quarterfinal classic at Wimbledon two years ago. Indeed, Baghdatis is no stranger to five-set tussles, though he's lost four of his past five.
Prediction: Baghdatis in four.
Juan Martin Del Potro (8) vs. Marin Cilic (19): These two 20-year-olds with similar styles and statures figure to be in the top 10 -- Del Potro is already there -- for years to come. Del Potro, the owner of a 23-match winning streak last summer, eased into the fourth round by overcoming big-serving lefty Gilles Muller. Cilic advanced smoothly, ousting fading bulldog David Ferrer. Neither has lost a competitive outing in 2009 and both are national No. 1s.
For what it's worth, Del Potro, an Argentine, won their two junior meetings, according to Cilic, a Croat.
"Yes, I remember," Del Potro said. "But we were younger. Now [we're 20] and the life changed too much. We don't know what can happen Sunday."
A win for Cilic, coached by veteran Bob Brett, and he's into the quarterfinals of a Grand Slam for the first time.
"I think I'm in a good way with my progress and my work," Cilic said.
Prediction: Del Potro in four.
Dinara Safina (3) vs. Alize Cornet (15): The bubbly Cornet caused a stir at the Hopman Cup in Perth, Australia, this month, sporting what was described as a transparent top and extra-short skirt. Perhaps she's following in the footsteps of fellow Frenchwoman Tatiana Golovin, who perennially opens eyes with her attire. Cornet, a crafty baseliner, downed last year's semifinalist, Daniela Hantuchova, in the third round. Safina, representing the family now that big brother Marat Safin was sent packing by Federer, has picked up her game since a first-round wobble. On a hard court, her power should be too much.
Prediction: Safina in two.
Ravi Ubha is a frequent contributor to ESPN.com.