You can trust Logan Webb’s breakout season

Logan Webb has arrived. The young right-hander for the San Francisco Giants commonly referred to as “Baby Ace” just had a breakout season in 2021, becoming one of the household names in baseball.

This was Webb’s third season in the major leagues; however, for the first time he delivered on the potential he has always shown flashes of, this time on a consistent basis. Alongside Kevin Gausman, Webb formed the one-two punch that carried the Giants rotation all season.

It’s easy to be a little leery of projecting that same type of production, and a natural evolution moving forward for Webb because of all the struggles he had in the previous two years, but here’s why that shouldn’t be the case.

The 2021 Logan Webb is not the same as the 19-20 version. His breakout didn’t come out of nowhere. There’s a clear path of adjustments and changes that led to this new level of performance.

Number 1: Pitch Usage

Here’s a graphic of his repertoire since his debut:

Credit: Baseball Savant

Webb primarily threw his four-seam fastball at a 43.8 and 33.7 percentage in ‘19 and ‘20, which was a big part of his problem, given that it was his worst pitch by run values.

With that pitch mix, his GB% hovered around 50.0, a rather unimpressive mark.

In 2020 opposing batters feasted off his four-seam fastball. Here are the numbers.:

90 PA

.329 BA

.507 SLG

.417 wOBA

All three of his other pitches discounting the cutter that he threw a mere 5.3% of the time had an xwOBA below .300:

Changeup: .298 (30.8%)

Slider: .295 (15.3%)

Sinker: .277 (14.8%)

A big part of his struggle came from not being able to keep the ball on the ground, which itself came from a high launch angle against his primary pitch at the time: the four-seamer.

2021: Living off the sinker

Webb entered the current season surrounded by question marks and although the Giants certainly didn’t expect to be in a position of contention at this level, his spot in the rotation was far from a guarantee. However, a really strong spring training was enough to give him one more shot at a starter’s role.

What did he do? Webb became basically a starter with a three-pitch mix.

The sinker, changeup, and slider accounted for a little under 90% of his pitches. The four-seamer is still a factor (especially against left-handed batters), but within his arsenal, it has a completely different role and subsequently a different impact. The cutter remained a nonfactor, really.

What’s so special about the sinker?

Although it’s the primary pitch, he doesn’t get a lot of whiffs on the sinker, which is common for that type of pitch. The whiff rate in ‘21 was just 16.0%.

What Webb does do so well with the pitch is not even that complicated. First, he limits hard contact; the sinker gave up an average exit velo of 87.8 MPH, better than the 90.1 against his four-seam fastball in the previous year. Webb also keeps the ball on the ground with a -5 launch angle against the sinker, which is a good sign for the pitcher.

Logan Webb’s sinker works well because of its outstanding vertical movement that leaves most batters at a loss.

Webb ranks in the:

98th percentile of Vertical Movement vs average (8.5)

99th percentile in % Sink vs average (37)

The only other pitcher in the big leagues that throws a sinker similar to Webb is another postseason standout; Tanner Houck from the Boston Red Sox. In every category from velocity to horizontal and vertical movement, they’re extremely similar.

There are a few caveats, though: Webb threw his sinker 834 times as his number one pitch while Houck used the sinker as a complementary weapon, throwing it 198 times.

Slider as the put-away pitch

Great pitchers can get you out in multiple ways, and you need a certain level of diversity to be successful as the starter. To fix his fastball issues, Webb adopted a three-pitch arsenal establishing the sinker and using the slider as the primary put-away pitch.

Chances are if you’re seeing a Logan Webb strikeout, it came on the slider. 88 of his 158 during this year came on the breaking ball.

As you were able to see earlier, opposing hitters didn’t have that much success against his off-speed stuff prior to 2021.

Webb decreased his changeup usage from 30.8 to 23.6 and increased the slider from 15.3 to 27.7.

That slider with roughly the same characteristics as in previous seasons became that much more successful, boasting a 47.1 Whiff%, not even close to the 28.3 number of the past year.

In summary, Webb went from being primarily a four-seam, changeup pitcher to a sinker, slider one, and not only the final results, but the peripherals and underlying numbers as well show that the move worked out.

You can determine from a very early stage whether a pitcher has great stuff or not; however, it’s a natural part of the process to work on it, make adjustments, make changes, and evolve as a starter.

To use an example, Blake Treinen after an outstanding career realized he needed to change something, so he developed a new slider, and off of that everything changed for him.

Baseball is unpredictable and anything can happen, but there’s no reason not to buy into the new Logan Webb. This newfound success didn’t come from nowhere. A calculated change in strategy helped Webb in reaching the next level