It is a weapon so lethal it could be licensed to kill. And last night John Isner freely admitted that for him, it's all about the serve.
The 28-year-old defeated Yen-Hsun Lu in the final of the Heineken Open yesterday and, typically for the American, won both sets on tiebreaks.
If Isner didn't possess the serve he does, he wouldn't be ranked inside the top 500 in the world. But as he showed against his Taiwanese opponent, he'll be up there with the best for as long as he can send down bomb after bomb at more than 200kmh.
Over the entire tournament Isner managed to break his opponent's serve in just three sets. He won five out of the six tiebreaks he played and served an incredible 79 aces in his four matches.
There wasn't a single break of serve in the final. In the first tiebreak, Isner got a mini break and held that lead for the rest of it. In the second he fell behind 3-0, but won when his opponent double-faulted and then sent a poor volley into the net on the third championship point.
This is Isner's second Heineken Open title - he won in 2010, before David Ferrer's domination.
"I knew it was a tough match and I didn't figure him coming out and not playing well today," Isner said. "I thought it was my best performance of the week, I was very happy with how I played, apart from all of the break points missed [10 in total].
"I felt like I was hitting the ball the best I'd hit it all week and that's a very good sign going forward.
"Just as always, I relied on my serve a lot. I wish it didn't have to be so close at the end, it gives me a lot of grey hairs but I'm so happy."
A week ago Isner had said he might not take part at the Heineken Open - he pulled out of the Hopman Cup in Perth the week before because of an ankle injury and even after he'd made the trip to Auckland he said there was some doubt about whether he'd make it on to court.
"To say this was unexpected coming into this tournament would be a huge understatement," he said.
"But sometimes that's how things work out. You come into something with low expectations and the pressure is off of you, but things tend to work out and that was the case this week, so I'm so happy."
Aside from in Auckland, Isner has never won a tournament outside America. So this victory does end a four-year barren period.
"I feel super comfortable here," he said. "The people are so nice, the food is great, the city is amazing and the people speak English, which helps.
"I don't feel like I'm so far away from home, like I actually am and this is a fantastic start to the season, just like it was in 2010.
"Winning a title doesn't happen all that often, I'm not a guy like Roger [Federer] who has 60 or 70 of them.
"So this feeling never gets old."
For Lu, this was the 30-year-old's first ever appearance in an ATP final and the next few months will determine whether this was a flash in the pan or the start of a new chapter in his career.
"I have nothing to complain about and nothing to talk bad about the match," Lu said. "He just served incredibly.
"There was one period of time where I couldn't read his serve. Even sometimes I guessed right, the speed of it meant that I couldn't get the ball back.
"But I started well, I pushed him to get one break point and there were some games where it was 0-30. But he's No 14 in the world, the main weapon for him is his serve. I had a great week and I'm happy with my performance, but I just hope that I can keep this going next week."
- Sunday Star Times