One hundred and five? No big deal.

"Yeah, I've seen it," said Red Sox closer Jonathan Papelbon.

The pitch the Red Sox' reliever was referring to was a 105 mph fastball thrown by Cincinnati rookie Aroldis Chapman last Friday. Papelbon's run-in with that kind of velocity? That came when the pitcher was clocking then-Detroit minor leaguer Joel Zumaya in the Florida State League, admittedly getting a radar gun reading of only 104 mph.

"What's the difference? David, what's the difference between 104 and 105? Nothing," Papelbon said, using teammate David Ortiz as a point of reference. "I've seen it. Ask [Dustin] Pedroia. Coming at 105, going out at 205."

Evidently, Papelbon knows fastballs.

It started when he was manning the radar gun for Jon Lester's starts during the pair's 2004 stint with Sarasota.

"I used to always calibrate our gun just to make sure," Papelbon explained. "I started and Lester started so I always had Lester's velocity as well. Zumaya was consistently 101 to 104."

Now the closer has a unique knowledge of how fast a fastball exactly is, and exactly what that might mean.

In short, Papelbon doesn't trust radar guns. He trusts himself.

"I can tell you exactly, within a mile an hour, what that fastball is just by the way it comes out of my hand," he said. "I know for a fact that I've been in plenty of stadiums where it's been 2-3 miles an hour faster, where the clock has rated it faster than what I think it is is. I don't trust radar guns. Radar guns are getting the velocity out of the hand. They're not getting the velocity at the plate and that is a HUGE difference. 

"You know the difference between a fastball out of the hand and a fastball that has life at the plate, it's huge. By the time it gets to the plate it's clocked 5-10 mph slower depending on how the ball comes out of the pitcher's hand. I want life at the plate. I don't want life out of the arm. I could care less. I want the ball to continue to generate power as it goes across the plate."

The pitcher has been reminded lately how important the end of a fastball is compared to where it originates. Papelbon had long been known for the last five feet of his heater, with the ball seemingly jumping up as it approached the hitter.

And while that dynamic had seemingly been inconsistent for much of the past few years, it has made a triumphant return as of late.

Wednesday night offered the latest example, with Papelbon using a mid-90's fastball that jumped on the Orioles' hitters, resulting in his 34th save of the season. It also just happened to be the four-year anniversary of when he suffered a subluxation in his right shoulder, when the reliever was forced to realize the importance of preparation and delivery.

For much of the first-half of this season, Papelbon was searching for the kind of velocity that elicited uneasy reaction from hitters and upper-90's readings on the radar gun.

Then, around the All-Star break, the closer found some answers to what he was doing wrong in his delivery and the result has been a familiar ally -- his old fastball.

For the season, Papelbon's heater is averaging approximately 95 mph, which is line with the best of his career. Since the break no Red Sox pitcher has notched more strikeouts per batter faced, or strikeouts per nine innings.

His swing-and-miss ratio with the fastball (22 percent) is still about 10 percent off from where it was at its peak, in 2007. But, nonetheless, Papelbon hasn't been this optimistic about his fastball in quite some time.

"Now I've got it back more than ever," Papelbon said. "It's all pitching mechanics. It's all delivery. It's all about how it's coming out of your hand and staying behind the baseball.

"My mechanics are better. My mechanics are smoother. They're more directed at the plate and I'm getting more drive out of my lower half."

It's an adjustment that those who know him best have been well aware of.

"He's driving down the mound more consistently rather than swinging open," Red Sox pitching coach John Farrell explained. "In the past he would have the tendency to be more rotation so when he would throw fastballs to lefties they would leak back over the plate. So it's created a little more power and that second gear through the strike zone. We're seeing it too, as a gauge with the numbers he's flashing up with his velocity."

Still, Papelbon offers a reminder: Look at the results, not the stadium's radar gun reading.

"You have to understand the ball loses velocity as it travels," he said, "and 105 could be 95 at the plate, and 95 could be 95 at the plate. I know."