Kansas City LHP Danny Duffy started the 2016 season as a member of the vaunted Royals bullpen, but injuries to starters Chris Young and Kris Medlen prompted the team to promote the lefty to the starting rotation. Since being moved out of the pen, Duffy has been phenomenal as a fill-in starter. Going into his Saturday start against the Tigers, since May 15th (Duffy’s first start) Danny was 4-1 with a 3.11 ERA, 1.02 WHIP, .228 opponent average, and a 73/12 K/BB ratio in 11 starts. It’s certainly been the best season of his young career so far and he’s got the supporting stats to suggest that it’s for real. There are, however, some things to consider before jumping to conclusions of him carrying your staff throughout the dog days of summer. Let’s take a closer look at Danny Duffy’s July 16th start on the road in Comerica Park against the righty-heavy lineup of the divisional rival Tigers with 13 HD GIFs.
First let’s look at Danny’s strikezone plot from the outing:
You can see how elevated Duffy was on Saturday with the Fastball. Both the Four-Seam and the Two-Seam were generally up in the zone throughout the start. In the beginning it was by design. Duffy loves to go upstairs with the high heat when he’s ahead. He did this constantly in the first three innings to get strikeouts. Later on, however, the elevated Fastballs were less about design and more about fatigue. The Changeup location was also hit and miss. When he did keep it down and arm-side it was deadly as a pairing with the Fastball, but he left a couple up in the zone over the middle of the plate that were ineffective.
Four-Seam Fastball
Duffy threw his Four-Seam Fastball 34 times while landing 25 of them for strikes. He averaged 94.2mph while topping out at 96.5mph with the pitch while also getting 6 whiffs (17.6%) on 17 swings. The Four-Seam is Duffy’s bread and butter. He’s lost some velocity on it since moving from the bullpen to the starting rotation but that doesn’t stop him from attacking with it relentlessly.
The gist of Danny’s Four-Seam can be seen on this 95mph offering that he spots on the inside corner to James McCann for strike one:
When Duffy gets ahead in the count, he loves to give hitters the high cheese with the Four-Seam Fastball. He gave McCann that treatment in the same at-bat as the GIF above, with this elevated 95mph Fastball for the swinging strikeout:
Why not make McCann the star of this whole section? This pitch is actually important for a couple reasons. Duffy was having trouble keeping his Fastball velocity up in the later stages of the game. When he did manage to touch 94-95 after the 5th inning, his command was off. As this pitch shows, Duffy gets bailed out of a potential bases loaded situation with no outs by getting James McCann to commit to this 95mph Fastball in on the hands:
Duffy managed to throw his Four-Seam for strikes 73.5% of the time and the 6 whiffs are encouraging, but his velocity dipped as his pitch count increased. He looked visibly tired from the 5th inning on and his Fastball was the first thing to go when the fatigue set in.
Two-Seam Fastball
Duffy totaled 32 Two-Seam Fastballs while getting 19 strikes in the process. The pitch averaged 93.8mph while maxing out at 95.9 and failed to get a whiff on 9 swings. The Two-Seam had the lowest strike % (59.4) of any pitch Duffy threw on Saturday.
Danny struggled to command the secondary Fastball, as we see here with this 90mph Two-Seam that just misses outside to Jose Iglesias:
When located, though, it can be a tough pitch to hit. This 95mph Two-Seamer that lands right on the outside black to Mike Aviles was one of Duffy’s best within the start:
Danny mixed his Two-Seam and Four-Seam fairly evenly against the Tigers (34 Four-Seam, 32 Two-Seam) despite favoring the Four-Seam more over the full season (43.7% Four-Seam vs 19.7% Two-Seam). This is likely due to the fact that he was facing a lineup that only featured one left-handed batter. It’s tough to tell when he’s throwing either, though, as neither often stands out based on movement. There were only a couple times when I was certain I was looking at a Two-Seam Fastball. It loses its tailing action when it isn’t located arm-side, which you can see Duffy had trouble achieving consistently in the plot above.
Slider
Danny tossed 25 Sliders and dropped 15 of them in for strikes. It’s his slowest pitch that he features as it averaged 81.4mph and topped out at 84.3mph on Saturday against Detroit. Only 1 of the 10 swings at the Slider generated a whiff.
The Slider comes with a nice tight break as we see with this well-located 83mph pitch to Victor Martinez on the outside black for strike one:
Duffy started to lean on the Slider later on in the outing as his Fastball command started to wane. He starts Nick Castellanos off with this 78mph Slider over the heart of the plate for a first pitch strike:
Like I said, he started to lean on the Slider, as he doubled up on it with the very next to Castellanos. This time, however, the Tigers third baseman was ready for the elevated breaking ball and smacked this 81mph Slider for a single:
One of my favorite pitches from the outing, and Duffy’s best Slider of the night, was this 84mph 1-1 offering to V-Mart that swept across the entirety of the plate for the called strike on the inside corner:
After using a slower Curveball throughout the majority of his career, Duffy seems set on using this quicker Slider as his go-to breaking ball. He’s completely ditched the Curve and moved the 20.0% usage directly to the Slider. It fits better with the high velocity Fastballs he features as it comes in on a flatter plane than a loopy Curve, making it tougher to identify out of the hand.
Changeup
Danny threw a total of just 13 Changeups in this outing but landed an impressive 10 of them for strikes. He averaged 84.2mph while maxing at 86.4mph with the pitch and earned 3 whiffs (23.1%) on just 9 swings with the offering.
The Royal lefty mixed in the Changeup early on, and located one beautifully to Victor Martinez here with this 86mph pitch that dips a great deal to get the swinging strikeout:
Duffy was far from perfect with his location on the Changeup, though, as we see in this next pitch. Ian Kinsler had Duffy’s number on Saturday. This 84mph Change-piece was left over the middle, rather than outside on the arm-side, and brings minimal movement to the plate before Kinsler launches it into orbit for a 2-run HR:
Let’s end it on a good note, and remind ourselves what a well-located Changeup can do to a right-handed hitter facing Duffy. This 85mph offering looks just like a Fastball all the way to the dish before simply disappearing beneath Cameron Maybin’s bat for the whiff and the swinging strike:
The 13 Changeups out of 104 total pitches (12.5% usage) is right in line with Duffy’s season total of 15.4% usage but I found it somewhat interesting that he didn’t try to mix in an increased amount against such a righty-heavy lineup. The early bomb to Kinsler might have steered Duffy away from the Change in favor of the Two-Seam Fastball that brings the same directional movement.
Final line: 6.1 IP, 6 Hs, 4 ER, 1 BBs (1 HBP), 7 Ks, W. 104 pitches (69 strikes), 14/26 first pitch strikes
So what do we take away from this? Duffy has been nothing short of amazing since he joined Kansas City’s starting rotation and has been a blessing for many fantasy owners in a season where starting pitching has been so erratic. The strikeouts are there and he isn’t walking batters (he’s sporting an insane 23.5 K-BB%). He’s currently enjoying career bests in every plate discipline statistic on Fangraphs. Hitters are swinging at his stuff at the highest rate of his career (51.8%) but making contact at the lowest rate of his career (73.2%). He’s also getting batters to chase at his offerings outside the zone more and generating less contact on those pitches.
Duffy also decided to ditch the windup and pitch strictly from the stretch as a starter regardless of the situation. He had tried a traditional windup delivery in 2015 but chose to stick to his roots and pitch exclusively out of the stretch this year which seems to be aiding him in his improvements.
So what gives? What’s not to like? Well for starters (heh), Duffy steadily lost velocity on his Fastball from the 5th inning on. While it’s possible that he was just pitching to contact with a 4-run lead, it’s odd that he only touched 94mph one time between the 5th and 6th inning. His average Fastball velocity was also down in this start (94.2) when compared to his season average (95.6). He did manage to ramp it back up to 95 in the 7th inning but his control was all over the place, and he may have been overthrowing as he was aware of his velocity dip. He looked visibly exhausted in the 6th and mixed in a noticeably increased share of off-speed to compensate for the lack of Fastball command. Danny had thrown over 100 pitches in all of his 4 previous starts as well, so this could all be coming from mounting pitch counts. But with an All Star break mixed in before this start, it’s something I’d be monitoring closely as a Duffy owner.
While Duffy has never exceeded 150 innings at the big league level, he sits at a mere 88.0 so far in 2016. I’d be more than happy to milk whatever remaining value he has for this year, but after seeing how tired he got after just 75 pitches on Saturday, with a full 8 days of rest between starts, I’d also be quick to deal him for the right piece if an owner is willing to pay for what Duffy’s already accomplished.
Let’s end this breakdown with one of Duffy’s best Fastballs in the outing. Danny blows this 96mph heater right past the terrifying bat of Miguel Cabrera for the swinging strikeout to end the inning – resulting in a very sad Miggy:
Ian Post contributes for Pitcher List and grew up on the game of baseball by playing year-round through adolescence and pitching in college before finding his love for writing about the sport. When he isn’t providing pitching analysis, he can be found faithfully rooting for the Mariners, watching Game of Thrones, and searching for a new favorite IPA in the Pacific Northwest. You can follow Ian on Twitter @TheDonGiggity.