Last 31 Day Starting Pitcher Velocity Increasers

As we often say, pitchers seemingly change much more quickly than hitters, so you need to be paying attention to any trends in velocity, pitch mix, spin rate, movement, etc. It’s therefore always a good idea to take a look at changes in the last month versus the rest of the season to potentially spot pitchers rising (or falling) to new levels of performance. With that in mind, let’s identify and discuss the starting pitchers whose four-seam fastball velocity has increased most over the last 31 days versus the rest of the season prior.

Brad Keller is no strikeout artist, as he relies more on inducing grounders and hoping his defense converts those balls into outs. But what if Keller was now a 95 MPH thrower, rather than 93+? Suddenly, his SwStk% is nearing double digits, and his strikeout rate has pushed above 20%. When you combine that with a ground ball tendency, which is vitally important in a season where 15% of fly balls have flown over the fence, you realize he has transformed himself into a potential mixed league asset, rather than a guy to avoid sitting with a 5.15 SIERA. This, of course, all hinges on his ability to sustain that velocity. Just like any skills changes, velocity spikes often don’t last, but sometimes they do! So all I could say is that if Keller can continue averaging 95 MPH with his fastball, you can ignore his season SIERA and consider him in your shallower mixed league. If the velocity proves to be temporary, I wouldn’t touch him regardless of league size and format (no matter how good you thing he might be at beating his expected ERA metrics, a 5.15 SIERA with well below average strikeouts is BAAAAAAAAAAD).

Are Yu back, Mr. Darvish?! Over his first eight starts, Yu Darvish was impossibly terribly, posting a 5.40 ERA and hilariously inflated 19.3% walk rate. While his mid-20% strikeout rate was pretty good, it represented a career low, and disappointing during his second tour of duty in the National League. Then he regained some control and his velocity spiked. While his SwStk% didn’t budge, his strikeout rate over these past 31 days has surged above 30%. That’s more like what we would have expected from vintage Darvish during a full season in the NL. Those who bought low (or picked him up via free agency) should be patting themselves on the back and continue to ride him the rest of the season.

Reynaldo Lopez was a weird sleeper entering the season. On the one hand, the guy averages the mid-90s with his fastball, a pitch that was graded a 70 back in 2017. That would excite anyone. On the other hand, his 3.91 ERA last season was a complete mirage, as it was a full run lower than his SIERA. Besides, that high octane fastball hasn’t actually translated into strikeouts, so this was all about blind optimism in the fastball velocity. It looks like over these past 31 days that Lopez may have finally figured something out making the blind optimists look good…eventually. His velocity has spiked, his SwStk% has skyrocketed, and his strikeout rate is finally in the mid-20% range, precisely where we had hoped it would eventually settle. With all three of his secondary pitches flashing SwStk% marks in the teens, there’s a real chance this new version is real.

Daniel Norris enjoyed a velocity spike in 2016, sustained it in 2017, then he completely lost it and still hasn’t regained it. It has hampered his chances at a true breakout, but he’s been clawing back the past 31 days. The velocity is up, the SwStk% is up, and his strikeout rate is back above 20%. It’s still not great, and that last 31 day SwStk% is actually just below the league average, but it does make him a viable option in deeper mixed and AL-Only leagues. Before, he was a ratio killer in which one would prefer a strong middle reliever instead.

I guess it’s a good thing that Zack Greinke’s velocity has rebounded back above 90 MPH, because falling below that important level would have likely accelerated his future decline. We see that the velocity rebound improved his SwStk%, but curiously, his strikeout rate barely increased. Like everyone else, it’ll be fun to see what, if any, changes the Astros make with his repertoire. It’s been just one start so far, but in that start, he threw his fastballs significantly less in favor of both his changeup and curve ball.

Ughhh, why am I torturing myself by including Chris Archer on this list? It’s nice to see Archer’s velocity improve, but 94.5 MPH is still nearly a mile per hour lower than where he sat last season and represents a career worst. His SwStk% didn’t move, but his strikeout rate increased a bit. For some reason, Archer suddenly can’t find the strike zone this year, which pairs poorly with a near 21% HR/FB rate. The amazing thing that most probably didn’t even realize is that his BABIP sits at just .277! The argument was always that his fastball stinks and being a two-pitch pitcher, he was easy to tee up and deserved an inflated BABIP. Oops. It comes down to his control and how much his HR/FB rate luck improves over the rest of the season.