Here are five takeaways from Day 2 in steamy Melbourne.
Harrison, Roddick shine at Hisense
Harrison will soon be joining the big-time.
Harrison didn't beat Murray, but what he did do was take a set off the world No. 4 -- and he wasn't bulldozed in the three that he lost. It was even more impressive than taking a set off Robin Soderling at the French Open and two off David Ferrer at Wimbledon last year. Murray is at another, higher, level.
Harrison's varied, mostly powerful game overwhelmed Murray in the first set, and he held a break point to take a 2-0 lead in the fourth. Had he converted, they might have gone the distance. Harrison, 19, said Sunday he was working on curbing his temper, and he indeed held it together for most of the bruising 3-hour, 12-minute encounter.
What cost the Louisiana native was getting broken early in the second and third sets. When he gets a little more experience, he'll buckle down and hold firm.
Murray came away impressed.
"I thought he was good," Murray said in his news conference. "He serves well. He's quick. He does everything pretty solid. There wasn't one thing in particular that was incredible, but there wasn't too many holes in his game, which, if you want to be a good player, you can't have any."
"I want him to play like that when he's not playing a top-10 player," Andy Roddick, a mentor to Harrison, said in a news conference. "If he does that, he won't be [ranked] 80th for too much longer."
Roddick watched parts of the match before confronting Robin Haase.
"He had a pretty good game plan," Roddick added. "I thought he went out and was pretty aggressive."
Roddick followed Harrison at Hisense Arena and put in a typical Roddick performance, holding firm to handle the more talented -- yet more unstable -- Haase in three sets.
Watching Stosur at the Australian Open, it's hard not to recall Frenchwoman Amelie Mauresmo -- another classy, likable Grand Slam winner who couldn't handle the pressure of competing at her home major. (Coincidentally, Mauresmo won her first Grand Slam title in Australia, while Stosur reached her first Grand Slam final in France.)
Stosur's first-round 7-6 (2), 6-3 loss to rejuvenated Romanian Sorana Cirstea extended her misery at the Australian Open; in 12 appearances she's never advanced to the quarterfinals, and her record slipped to a mediocre 14-12.
At least the Aussies still have Tomic.
Like Mauresmo in defeat at Roland Garros, Stosur spoke calmly and eloquently following the match. There was no hiding. The sixth seed freely admitted that nerves got the better of her.
"I think for sure it affects you physically," Stosur said. "Physically I think it's easy to see that you tighten up, your shoulders do get tight, you don't hit through the ball."
Stosur's immediate plans were to take "at least a few days off, get away, try and not think about it, kind of forget about what's happened a little bit."
She may be a three-time Grand Slam champion, fine competitor and the fourth seed, but Maria Sharapova isn't one of the favorites at the Australian Open. Perhaps that suits her.
Hindered by an ankle injury and still trying to lessen the double faults, Sharapova began with a crushing 6-0, 6-1 win over Argentine Gisela Dulko, a player who has earned a reputation for cutting down big names at majors. Dulko toppled Sharapova, in fact, in their previous meeting at Wimbledon.
"She can definitely play some really good tennis," Sharapova said in her news conference. "I think I was just mentally prepared for that."
If Dulko is the known, Sharapova's next opponent, 22-year-old American Jamie Hampton, is the unknown. And that could be tricky for Sharapova. She was almost undone by Caroline Garcia, a promising yet little-known youngster, at last year's French Open.
"I think my coach will do a little scouting," Sharapova said.
Unlike Sharapova, Petra Kvitova is most certainly one of the top contenders. Her first-round performance wouldn't have changed anyone's mind. Kvitova, the second seed, dismantled Russian veteran Vera Dushevina 6-2, 6-0, winning the final 12 games.
But what would a Kvitova match be without a trough?
Kvitova hit three double faults in the second game, getting broken to fall behind 2-0.
"I think that I can improve for sure my serve," Kvitova said.
Spaniard Carla Suarez Navarro will attempt to derail Kvitova in the second round. Although her top results have come on clay, Suarez Navarro ousted Venus Williams in Melbourne in 2009.
From Russia with no love
But the Russian men are fading fast.
Youzhny, who has nose-dived after sparkling in 2010, lost in five hours to Andrey Golubev -- who formerly represented Russia -- in what was arguably the match of the tournament so far.
Russia's lone men's winner was Alex Bogomolov Jr. -- who switched allegiances from the U.S. to Russia late last year.
After saying last week that he considered taking legal action against the USTA when he was ordered to repay them $75,000 for making the move, Bogomolov Jr. now claims he harbors no ill feeling toward the U.S. governing body. He sent the USTA a check at the end of December.
"They invested their time and finances in me," Bogomolov Jr. said in his news conference. "I think it was only right for me to pay them back."
London-based Ravi Ubha covers soccer and tennis for ESPN.com. You can follow him on Twitter.