Zack Greinke: Fastball-Cutter Combination Sparks Success

Zack Greinke produced his fifth consecutive win of the season last Saturday night, tossing a complete game shutout that included nine strikeouts, two hits and one walk at home against the Colorado Rockies. This outing generated the highest game score (91) of his career.

Missing a large portion of his season with a broken collarbone, the Dodgers have patiently waited for Greinke to pitch up to the level of the six-year, $147 million contract he signed with the club last December. Over his last five starts, the former Cy Young Award winner has certainly performed up to that billing, at least compared to the outings preceding his victories streak.

Since his streak began on June 22, Greinke has a 2.50 ERA and a 1.06 WHIP. Prior to the streak, Greinke had a 4.22 ERA and 1.41 WHIP.

Something has clearly changed for the veteran 29-year-old over his past five outings.

It's all started with his fastball-cutter combination against right-handed opponents.

Greinke's Improved Command

Fastball pitch frequency vs. right-handed hitters

At the beginning of the season - Greinke struggled to command his fastball within the zone. His zone rate sat at 51.4 percent and his called-strike rate settled at a meager 31.7 percent.

Over the last five games - His fastball has been consistently placed low-and-away to right-handed hitters  and with it he has witnessed his zone rate increase to 58.2 percent and called-strike rate to 47.5 percent.

Results of Greinke's improved fastball command

	April 5 - June 16	June 22 - July 13
In-play%	42.6%	42.6%
BABIP	.425	.120
SLG%	.438	.246

• Right-handers have tallied just one extra-base hit vs. Greinke's fastball since June 22, en route to a .246 slugging percentage that's nearly half the .412 league average.

Change in approach

Greinke's cutter is commonly mistaken for a slider and because he's commanding his fastball more consistently within the zone, both pitches become more effective..

Pitch Frequency of Greinke's cutter vs. right-handed batters

• Though Greinke commanded his cutter well -- locating the pitch for a called strike on the outer-ish belt-high portion of the plate or low-and-away far corner -- prior to his wins streak, unsurprisingly he did not induce many swings-and-misses with the pitch, evidenced by a miss rate of 42.9 percent chase rate.
• During his wins streak, though, opponents have missed a remarkable 63.6 percent of cutters located out of the zone. The league average over that span is 36.3 percent.

Changing Results

Comparing results of Greinke's cutter

	April 5 – June 16	June 22 – July 13
In-play %	37.1%	28.6%
BABIP	.455	.250
SLG%	.654	.154

• Right-handers' in-play rate against Greinke's cutter has decreased substantially to 28.6 percent during his streak, considerably lower than the league average of 46.6 percent.
• A product of that dwindling in-play rate, right-handers' BABIP has decreased to .250 and their slugging percentage has decreased to a lowly .154.

Key to Success?

Because Greinke has spotted his fastball more consistently within the strike zone against right-handed hitters during his wins streak, his changing cutter approach has coaxed righties into expanding the strike zone at a more frequent rate, leading to more swings-and-misses with his cutter out of the zone.

This two-pitch tandem will be key to Greinke's success moving forward, and could play a deciding role in the Dodgers' run at an NL West title.