Atlanta closer Craig Kimbrel is the National League’s 2011 Rookie of the Year, becoming the 10th relief pitcher to win the award in either league. And though his season had a sour end, Kimbrel had an absolutely spectacular year. Getting past his blown save in the 162nd game, we see that he had one of the more impressive relief seasons in recent memory:

(minimum 50 innings pitched)

Rank K% 6th* FIP 4th* xFIP 2nd**

*Since 1900

**Since 2002, when BIS batted ball data first became available

Perhaps looking at Kimbrel’s pitches through PITCHf/x will make his year look even more impressive.

Kimbrel turned to his four-seam fastball 70% of the time last year. His heater tails about 6 inches in on right-handed hitters, and it averages around 96 mph — though he registered as high as 100 mph, according to the Turner Field PITCHf/x cameras. His rate of swinging strikes on that pitch was as high as many pitchers’ breaking pitches.

Pitch # Whiff% Rank FF 899 .325 4th

The only four-seamers that were harder to hit this year belonged to Vinnie Pestano (.402), Kenley Jansen (.380), and Tyler Clippard (.361).

His fastball is great, but Kimbrel’s power curve might be even more lethal. And when I say “power curve,” I mean lots of power. At just less than 87 mph, Kimbrel throws the hardest curveball in the majors. It’s so hard that it’s often called a slider (the PITCHf/x algorithm labels it as such), but Kimbrel uses a spike grip and generates as much topspin as the league-average curve. The graph below shows the average velocities and vertical-spin deflections (relative to a spinless pitch) for sliders and curveballs in 2011. Kimbrel’s curve is the big outlier (highlighted in red), with slider velocity but curveball action.

Kimbrel’s combination of velocity and movement helps give him another dynamite offering.

Pitch # Whiff% Rank CU 393 .563 4th

The “rank” in this case compares Kimbrel’s curveball to other offspeed and breaking pitches (minimum of 100 swings against). The breaking pitches belonging to Jonny Venters (.720), Sergio Santos (.631) and Al Alburquerque (.586) are the ones with a better whiff rate than Kimbrel’s curve.

Considering Kimbrel is a two-pitch pitcher, the pitch frequency by count column chart is pretty straightforward. He loves throwing his fastball (and why not?), and he’ll throw it with great frequency when he’s ahead in the count — particularly to righties.

Kimbrel throws two pitches, and they’re both elite. Perhaps even more impressive is that he’s only 23 years old — meaning Kimbrel should be a dominant force in the Braves’ bullpen (along with fellow fireballer Jonny Venters) for years to come.