The best-kept secret on MLB's top team is ...

The story of the Giants' season, obviously, is that they have surprised just about everyone by maintaining not only their spot atop the NL West but also the best record in baseball. When that happens, there's typically a lot of internet ink spilled on the "how"s, the "why"s and, especially, the "who"s -- as in, the players behind the performance.

The Giants are no exception. There have been plenty of stories about how the aging core of Buster Posey, Brandon Crawford and Brandon Belt has rediscovered its peak form together for the first time in years.

Same goes for why the Farhan Zaidi- and Gabe Kapler-led regime has an uncanny ability to get the most out of overlooked and castoff position players, like Mike Yastrzemski, Alex Dickerson, Darin Ruf and LaMonte Wade Jr. And don't forget about the club figuring out how to help pitchers in much the same way, like the staff has done for starters Kevin Gausman, Anthony DeSclafani, Johnny Cueto and Alex Wood.

But there's one Giants player whose breakout campaign has flown so far under the radar that you may not be familiar with him at all.

Meet Logan Webb, who is perhaps the biggest surprise on baseball's most surprising team, the club's lone homegrown rotation member and the first starter San Francisco has developed successfully since the dynasty days of Matt Cain, Tim Lincecum and Madison Bumgarner.

Selected in the fourth round out of Rocklin High School in California way back in 2014, Webb still is only 24 years old as he is starting to come into his own. The right-hander's rise through the Minor Leagues was halted by Tommy John surgery while he was in A-ball in the middle of 2016. Webb pitched very well upon returning, climbing to No. 5 among Giants prospects entering the 2019 season and restoring the organization's faith in him, which was rewarded when he made his MLB debut in August of 2019 -- little more than three years after the procedure.

Over his first 21 career outings in the big leagues across '19 and '20, however, he sported a 5.36 ERA, but his 4.15 FIP at least indicated there were some underlying skills.

"My main goal coming into the season," Webb said during Spring Training this year, "was just to kind of show that I am better than what I showed the last two years."

Webb has done just that, entering tonight's start against the Mets with a 2.96 ERA, a 1.14 WHIP and a 9.5 K/9 rate in 85 innings across 17 games (16 starts). But how has he put together such a strong season so far?

Start here: Webb got knocked around May 5 (albeit at Coors Field), which actually put his status in the rotation in doubt at the time. Since that date, though? His 1.53 ERA is second among all pitchers to throw at least 40 innings and make at least four starts in that span, behind someone you might've heard -- Jacob deGrom.

Granted, the sample size is small -- only 53 innings -- because Webb had two stints on the injured list for a right shoulder strain that cost him the month of June. But any time a pitcher ranks right behind deGrom, well, you tend to take notice.

Webb has found success by taking a different path. While many pitchers recently have been turned on to throwing four-seam fastballs, especially elevated and with high spin rates, Webb -- known for his heavy heater in his prospect days -- has transitioned away from four seams and focused on just two in the form of a sinker. Oh, and his fastball is the opposite of high spin; in fact, it's in the seventh percentile among all pitchers.

Webb's Four-Seamer% vs. Sinker%, by Season
2019: 43.8 % vs. 12.6%
2020: 33.7% vs. 14.9%
2021: 12.5% vs. 33.7%

If you prefer to see this presented visually a different way, take a gander and note how the red line (four-seam fastball) and orange line (sinker) have gone in opposite directions:

That change in approach has helped Webb become one of the best groundball-getters in the Majors. Spurred by that low spin rate on his sinker, his 61.3 percent groundball rate ranks third among all pitchers with at least 200 batted balls against this year.

Such a style of pitching tends to avoid damaging home runs, and that has been the case for Webb, who has permitted just seven long balls. Only three pitchers have thrown at least 80 innings and allowed fewer dingers than Webb has: NL Rookie of the Year candidate Trevor Rogers, 2021 breakout ace Corbin Burnes and, yep, that deGrom guy.

There's more, too, because it's not like Webb is only getting grounders and limiting long balls. He's also striking batters out at a solid 25.9 percent rate, making him one of only five starting pitchers (minimum 80 IP) with a groundball rate of 50 percent or higher and a strikeout rate above 25 percent. The others? Burnes, Germán Márquez, Lance McCullers Jr. and Yusei Kikuchi. Pretty good company, and further evidence that when a pitcher can do both those things -- rack up worm-burners and whiffs -- it's a recipe for a breakout.

Webb's slider has become the best of his primary pitches, registering a .141 batting average against (13-for-92), a .193 wOBA (.224 xwOBA) and an impressive 46.9 percent whiff rate. That's the pitch he tends to go to when he wants a strikeout, and it gets the job done with a putaway percentage of 30.9 -- fifth best among starters.

Highest Slider Putaway%, by Starting Pitchers
*Minimum 100 two-strike sliders thrown
Jacob deGrom: 39.9%
Clayton Kershaw: 34.7%
Germán Márquez: 32.2%
JT Brubaker: 31.9%
Logan Webb: 30.9%
Alex Wood: 30.7%
Carlos Rodón: 30.6%
Freddy Peralta: 29.9%

Again, you're probably catching onto the theme that this list features big names and hurlers having impressive seasons.

Clearly, Webb will be an important piece for the Giants down the stretch as they aim to fend off the rival Dodgers -- against whom he's allowed five runs on only seven hits with a 17-to-4 strikeout-to-walk ratio in 16 innings over three starts this year -- to secure their first NL West division crown since 2012. Looking beyond '21, he'll be a key building block, too, given that all four of the other rotation members could hit the open market this offseason.

Put everything together -- the transition to the sinker, the ability to get lots of grounders, plus a putaway pitch to rack up strikeouts -- and Webb ranks in the top 15 in xSLG (.342, 15th), the top 25 in xwOBA (.289, 24th) and the top 25 in xERA (3.53, 24th) among 138 pitchers with at least 200 balls in play this season.

When you break it down that way, maybe what Webb's doing shouldn't be so surprising after all.