Wimbledon is two days old and the biggest surprise so far has been the weather — not a drop of rain has fallen at the All England Club — followed by the early dismissals of fourth seed Nikolay Davydenko (he never has taken to grass) and former finalist David Nalbandian (who finds himself in a typical mid-season swoon). The tournament ought to heat up today with a fine second-round match between Novak Djokovic, a semifinalist last year, and the ever-entertaining Marat Safin, who hasn’t cleared the third round at Wimbledon since 2001. Here are 10 things to look out for as the tournament progresses.

1. Andy Roddick’s Shoulder

Roddick, who defeated Eduardo Schwank 7-5, 6-4, 7-6(0) in the first round yesterday, has an excellent draw at Wimbledon this year, and he should be brimming with confidence after beating Roger Federer, Rafael Nadal, and Novak Djokovic earlier in the year on hard courts. Unfortunately for Roddick, a right-shoulder strain limited his practice leading up to the tournament and it may ail him further as the tournament goes on. Now that Davydenko has lost, the highest-ranked player standing between Roddick and the semifinals is no. 9 James Blake, who also won yesterday but usually disappoints on grass. We’ll learn a lot more about Roddick’s form in the second round when he plays Janko Tipsarevic, the versatile Serb who pushed Federer to five sets at the Australian Open and reached the fourth round at Wimbledon last year.

2. Ernests Gulbis

If this were 2005, Gulbis, the long, powerful Latvian teenager, would be the insider’s pick to upset Rafael Nadal in the second round. Luckily for Nadal, it’s not 2005, and he’s no longer a flawed grass-court player, but the second-best in the business. Gulbis will need to play the match of his life to win, as Jo-Wilfried Tsonga, a man with similar firepower, did to beat Nadal in Australia. No doubt Gulbis believes he can win — he’s got the confidence of a far more accomplished player. Is he ready for a shocker after his quarterfinal run at the French Open?

3. Hawk-Eye

Two British scientists recently released a study that calls into question the accuracy of the Hawk-Eye line-calling technology, which is used for instant replay. Maybe it’s not as accurate as advertised, but I do know this: It’s more accurate than the human eye. Why not use it? If players disagree with it and argue about it — as Roger Federer did in last year’s Wimbledon final, when he asked the chair umpire to turn off the machine — that’s fine (the drama is good for the sport, and no different from the drama we’d have without the technology). I’d rather trust Hawk-Eye than a linesman or chair umpire who is asked to watch a ball that whizzes back and forth at upward of 145 mph and decide whether it grazed a thin white line.

4. Dynasty in Decline?

I’m not talking about Roger Federer here, but twins Bob and Mike Bryan. Despite dominating the Davis Cup last year and playing some great tennis this year, they’ve fallen short in five of their eight finals and haven’t won a major title since the 2007 Australian Open. The twins, who turned 30 in April, have been ranked no. 1 in doubles since November 2005. How much time do they have left at the top?

5. Fewer Aces

The men throw down more aces at Wimbledon than they do at the other three majors, but I’m guessing this year’s numbers are going to come in low now that Ivo Karlovic and John Isner have lost in the first round. Interesting how the serve, once the most feared stroke among tennis fans for its capacity to bore everyone to tears, has not become the dominant shot everyone thought it would become.

6. Another Serbian Champ?

First Novak Djokovic won the Australian Open. Then Ana Ivanovic won the French Open. Is it Jelena Jankovic’s turn to win Wimbledon? Jankovic doesn’t have a serve, but she looked comfortable on grass during her 6-3, 6-2 first-round victory yesterday.

7. Olympic Preview

Venus and Serena Williams haven’t won a doubles title since 2003; at Wimbledon last year, they defaulted after Serena injured herself. The sisters won their first doubles match yesterday 6-0, 6-3 and might stick around longer this year so they can hone their skills for the Olympics in Beijing. They could also play each other in the singles final, which means Team Williams might well take home three of the four trophies awarded in women’s singles and doubles.

8. Another Russian

Russia continues to produce top talent, the latest being Anastasia Pavlyuchenkova, a 16-year-old who was the world’s top junior and is now in the second round of a major tournament for the first time in her career.

9. Awful Brits

If looking at Pavlyuchenkova and other Russian tennis stars makes you feel bad about the pace of tennis development in America, cheer up and look across the pond at Great Britain, home of one truly competitive tennis player (Andy Murray). Venus Williams beat Britain’s Naomi Cavaday in the first round and ought to pummel another Brit, Anne Keothavong, in the second round.

10. Stray Bullets

If you’re attending Wimbledon this year, you’ll be interested to know that the All England Club has hired sharp shooters to assassinate pigeons — that is, if the two hawks who reside at the club during don’t get the job done first. You’ve been warned.

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