LONDON -- It was a moment tailor made for that mythic Wimbledon creature, the Ace Monster.
The fleet and graceful Tommy Haas had diligently crept back from a two-sets-to-none deficit in his second-round match at Wimbledon against No. 7 seed Milos Raonic. Haas then managed to push the fourth set to a tiebreaker. It was touch and go, but with a slim 4-3 lead, Raonic fired his 28th ace of the match -- wham! -- down the center. Raonic then sliced another ace -- whoosh! -- out wide. Haas was cooked. Everyone on Court No. 1 on this day of stifling heat knew it.
"I wish I had a serve like that just one time in a match just to see how that would feel," said Haas, the oft-injured 37-year-old who was beaten by Raonic 6-0, 6-2, 6-7 (5), 7-6 (4). "I was joking during my last surgery on my shoulder that maybe we can put some titanium in there where I can maybe just get more speed, but it wasn't possible."
Can this be the year the ultimate grass-court predator, the man with the unreturnable serve, returns to the spotlight? The ambient conditions certainly seem favorable. Sam Querrey, one of those Ace Monsters, added an additional, significant six pounds of tension to his strings before his first-round match Monday because of the dry, warm conditions. He ended up serving 30 aces.
"If it were cool and overcast and I had used lower tension, I would have had maybe 15," Querrey told ESPN.com.
The ATP players fired down an astonishing 1,404 aces through the first full round of play, which ended late Tuesday night.
And with half the second round completed Wednesday, we pinpointed six servers in search of a Grand Slam title:
1. Milos Raonic
He detonated the third-fastest serve ever recorded at Wimbledon in his win over Haas, a 145-mph fireball (three mph shy of Taylor Dent's record). That's bad news for everyone else in the draw, including his next opponent and fellow ace machine, Nick Kyrgios.
Raonic is the highest seed among the Ace Monsters. But if he goes deep, it won't be simply because his ordnance is so big, but because the cannon is now supported on a strong, mobile platform. The lesson of recent years at Wimbledon is that even an exceptional server now needs more than a hammer in his toolbox. It can be a hard one to learn for a young man accustomed to blasting junior rivals to smithereens with his serve.
"It took me some more time to sort of figure out the rest of my game, and how to find that tennis identity," the 24-year-old said. "After I was able to clarify what my strengths are, and how to use them, I think I made good progress forward on grass."
You don't hear very much about 6-foot-8 Anderson, but he's a lean, mean serving machine. And with his South African heritage, it's a sure bet he's willing and able to follow where that serve leads -- to the net. Anderson has issued aces like an ATM spits out 10-dollar bills. He's tallied 57 in his two wins thus far. Can he be the next Kevin Curren?
3. John Isner
He handled Aussie Matthew Ebden in straight sets in the second round, firing 23 aces. The win put Isner in the black at Wimbledon for the first time in his career, with a record of 7-6.
True, he's had some rotten luck in years past at Wimbledon, including a knee injury and that 70-68 first-round epic in 2010 that killed his chances to advance. This may be the year Isner's luck turns. His third-round opponent, Marin Cilic, no serving slouch himself, will be coming off a debilitating five-set win in Wednesday's heat.
4. Nick Kyrgios
The overnight sensation has a serve as big as his personality. He pumped out a relatively modest number of aces in the first two rounds (28), but he's got the leverage as well as the arm to fire a much higher amount. Perhaps he should take a leaf from the playbook of his next opponent, Raonic, who said:
"Before, I thought I could get away with just throwing [the serve] down just because it's grass, and sort of slide it away from the guy. Then last year I learned quite a bit how important it is to keep going for it full out, all the time. Not flat, but high paced."
5. Sam Querrey
The American said: "Part of the problem for big servers like me is that the top guys are also maybe the best returners. That wasn't always true in years past."
Querrey has been playing well. He will get to see just how well when he meets Roger Federer in the second round Thursday.
6. Ivo Karlovic
He deserves mention because, perhaps more than any other player, Karlovic is proud to be an Ace Monster. He set a new record for aces (45) in a three-set match just a few weeks ago and says he likes to hit the unreturnables -- because then he doesn't have to volley.
Karlovic's logic is impeccable, even if the rest of his game is not. But you know how it is with these guys. We don't listen to them for their logic -- or watch them for their drop shots.