MELBOURNE, Australia — Since Lindsay Davenport returned to the tour last fall, the story of her comeback has been mostly about her motherhood and less about her tennis. She’s only lost one match in 20 tries, but most of those opponents were not heavy hitters with the exception of Jelena Jankovic, who played 15 matches too many last year and seemed to move at half speed as the season ended. The fact that Davenport played at all less than a year after having a son was the important thing. Fans have embraced her return, and she still can’t stop smiling and giggling when she gives interviews about her son, Jagger. Her colleagues are, to a woman, astonished that she began playing so soon after giving birth. They, like the rest of us, wonder how far Davenport can go and for how long.

On Wednesday in Melbourne, we’ll find out a lot more about where the new Davenport — happy as can be and more relaxed than ever — stands in the world of tennis. The 31-year-old will have her first real test since her return, a rare early contest of titans, when she takes on no. 5 seed Maria Sharapova in the second round. The tone of this match will be different from any match Davenport has played since the 2006 u.S. Open, when Justine Henin knocked her out of the tournament. She’ll have to adjust to the pace of Sharapova’s shots and her intensity, and she’ll have to hit the ball more cleanly than she did in her first-round match on Monday against Sara Errani of Italy, the no. 65 player in the world, against whom Davenport struggled mightily before prevailing 6–2, 3–6, 7–5 in two hours and 20 minutes. She admitted that she was both nervous to return to a Grand Slam event and perhaps too eager to play Sharapova.

“It will be the first Grand Slam winner I’ve played since being back,” Davenport said. “It’s one of the few players I don’t have a winning record against in the draw. She’s a great player — we play similar styles. She’s outplayed me the last couple of times we played.”

Sharapova and Davenport are indeed similar players, in part because of their physical strengths and weaknesses (tall, broadshouldered, and strong, but not fast or quick) and in part because they each learned to hit the ball from technique expert Robert Lansdorp. Sharapova described Davenport as a “one-two combination” player — in other words, hit a powerful serve or return and then follow it up with a penetrating forehand. Sharapova could be described the same way, though she has several advantages over Davenport, the most obvious being 11 fewer years of wear and tear. She also plays with more conviction than Davenport, who in the past was likely to mope when things did not go her way.

As eager as Davenport might be to prove she’s a threat to the game’s best players, Sharapova has a lot more on the line in Melbourne this week. Last year, she showed grit in reaching the final after nearly losing in the first round to an inferior opponent in extreme heat. But once there, Sharapova had no chance against an invigorated Serena Williams, who pummeled her 6–1, 6–2. The loss raised questions about Sharapova’s long-term prospects, and she didn’t do much the rest of the season to quell those concerns. Her shoulder ached for most of the year, and she spent a lot of time resting rather than training. Against the best players on the tour, she didn’t perform well (0–2 against Serena Williams, 1–1 against Venus Williams with a resounding defeat at Wimbledon, 1–2 against Ana Ivanovic, and 0–1 against Jelena Jankovic).

Sharapova said last year is behind her. More important, her shoulder, which she treats twice a day, doesn’t worry her anymore. She also finished off 2007 with her best match of the season, a narrow defeat against Justine Henin in the final of the season-ending championships in Madrid (it might have been the best match of the year on the tour).

“The whole week [in Madrid] was just a great relief for me because I was very close to just saying, ‘This was not my year,'” Sharapova said. “I kept having little setbacks where I would train for a few days and then had to stop for a week. That’s not the way you’re going to become no. 1 again. I just thought of maybe going on vacation. But I kept going.”

Lansdorp, in a recent conversation, described Sharapova’s play in Madrid as “unbelievable” (he no longer works with her). He also said he wouldn’t be surprised to see Sharapova on top again one day.

She has a great chance to do it, largely because the players who give her the most trouble — the Williams sisters and Henin — are older than she is. Jankovic and Ivanovic either don’t have the speed to neutralize Sharapova’s shots (Ivanovic) or don’t serve well enough (Jankovic). Several younger players, like Agnes Szavay and Agnieszka Radwanska, could contend in years to come, but it’s a little early to tell where they stand.

Davenport, of course, stands above Sharapova at the moment — she has won three major titles to Sharapova’s two and has spent many more weeks at no. 1 — and that in itself is a surprise. When Sharapova won Wimbledon in 2004 at age 17, beating Davenport along the way, she seemed destined to surpass a player like Davenport in short order and dominate the game for years to come. Three years later, she’s still waiting for her time. It would be a setback if Davenport made her wait even longer.

Mr. Perrotta is a senior editor at Tennis Magazine. He can be reached at tperrotta@tennismagazine.com.