A bat tweak -- the size of a hockey puck -- has made all the difference for Soto

The master craftsman changed his tools. Juan Soto, in his neverending quest for hitting perfection, started swinging new lumber this season.

Soto has spent nearly a decade in the big leagues establishing himself as one of the greatest hitters of his generation. Over that time -- although he cycled through different bat manufacturers, from Old Hickory to Victus to Chandler -- the physical construction of those bats never fundamentally changed.

"Never," Soto said recently at Citi Field. "I never tried anything different at all. It's always been the same model in my bats. Definitely some companies do it differently than others, but I was always trying to find the best balance in my bats, and actually the hardest wood. But it's been the same model since Day 1."

That all changed a few months ago. In mid-May, Soto started experimenting with a "hockey puck" knob bat. Those are the bats with the thick cylindrical knobs that we're starting to see more and more around baseball. The puck knob counterbalances the weight of the barrel, and hitters who use it feel like they can whip the bat around quicker.

Soto first used the puck knob as early as the Mets' series against the D-backs on May 9, and he used it almost exclusively from the Mets' series against the Marlins that began on May 22 through the All-Star Game.

So why did he do it? Soto had a hypothesis, and he decided it was worth testing.

"I feel like I can be quicker, especially on two strikes," Soto told SNY's Chelsea Janes after making the switch.

It should be no surprise that the impetus for Soto's change was two-strike hitting. Soto's two-strike approach is legendary. It is what makes Soto Soto.

The baseball bat is an extension of the hitter. Soto's switch to the puck knob-style bat was an effort to bring him and his bat into further harmony. Not to give him a dimension as a hitter that he previously lacked, but to augment his own best qualities at the plate.

Over the two months following the change, we got some measurable results for Soto's experiment. And it worked pretty much exactly the way Soto intended.

Soto after switching to bat with puck knob

• Overall swing length: 7.2 feet --> 7.0 feet
• 2-strike swing length: 7.0 feet --> 6.8 feet

Statcast measures a hitter's swing length as the distance the barrel of the bat travels from the start of the swing up until contact. Using the new bat, Soto's swing got shorter. His bat path got more direct to the ball.

Soto, in general, has a short swing for a player who is an elite slugger. Power hitters tend to have long swings that allow them to generate high bat speed, like Aaron Judge or Shohei Ohtani. But Soto is just as much an elite contact hitter as he is an elite power hitter. He has the swing to match, and he wants the bat to match, too.

"I think the balance of it helps me a lot," Soto said. "Definitely I'm all about balance with my bats. We started talking [with the Mets] about how we can get more balance in my bat, but so it actually doesn't lose the thickness and how hard the ball can jump off of the bat. So we've been just messing around with it and it feels great."

It is particularly important for Soto to shorten his swing with two strikes, so he can battle the pitcher as best he can. The hockey puck knob bat is a weapon designed precisely for that battle. A swing length under 7 feet is quite short, and that's the territory Soto got his two-strike hacks into.

"I just feel like I can handle the bat and control it a little bit better," Soto said. "You're not always gonna take the best swing, you're not always gonna have perfect timing. You've got to adjust to curveballs, changeups, sliders. And while you're waiting for the fastball, you've got to be able to make adjustments and whip the bat as smooth as you can."

Here's the type of swing Soto was pulling off with the puck knob bat. On May 22, just after he switched over to it, Soto belted a two-strike home run off a 100 mph fastball from the Marlins' Eury Pérez. His swing length was just 6.6 feet -- an extremely short swing to produce the explosive contact that came off Soto's bat, a 449-foot homer.

That type of swing explains the "why" behind Soto's bat switch. But there's a followup. Why now? After all these years with one style of bat?

"I don't know," Soto said with a laugh. "I just felt like I wanted different results. I always want to increase my good swings and my hard contacts. I was actually just trying to find a way, you know? I never trusted [changing my bat model] before. This year, I'm more open to seeing how it can help me be more successful."

Soto's normal bat, with the traditional knob, measures 34 inches long and weighs 31 ounces. The hockey puck knob model adds half an inch in length, and an ounce and a half in weight, taking the bat to 34 1/2 inches and 32 1/2 ounces. But it feels lighter for Soto to swing, quicker, more maneuverable, because the weight is concentrated down under his hands as opposed to at the head of the bat as it swings through the air.

You might not expect a player like Soto, famed for the consistency of his routine, to make such a change in his equipment. But Soto is not the first hitting genius to make even this exact change -- Joey Votto did it, too, and so did other great hitters such as Nolan Arenado and Paul Goldschmidt.

And the adjustments Soto was able to implement in his swing using that new bat paid immediate dividends. Once he switched fully over to the hockey puck knob, Soto was one of the very best two-strike hitters in baseball for the rest of the first half.

Soto's 2-strike numbers after switching bats

• OPS: .567 --> .819
• Expected OPS based on contact quality: .619 --> .896
• Swing-and-miss rate: 27% --> 14%
• Strikeout rate: 38% --> 21%
• Squared-up contact per swing: 34% --> 44%
• Blasts per swing: 13% --> 21%
• Batting value: +1 run created --> +13 runs created

Soto did more damage, whiffed less and struck out less. His normal numbers were terrific, and the numbers he deserved based on his quality of contact were even better. Major League hitters overall have a .510 OPS with two strikes this season; Soto's shot up to over 300 points higher than that after his bat switch, and was one of the best marks in the league. The only better two-strike hitter from a contact quality standpoint was Yordan Alvarez.

Highest expected 2-strike OPS, May 22 through All-Star break
Min. 75 plate appearances decided with 2 strikes

1. Yordan Alvarez, HOU: 1.018
2. Juan Soto: .896
3. Lars Nootbaar, STL: .807
4. Miguel Vargas, CWS: .776
5. Fernando Tatis Jr., SD: .775

Highest actual 2-strike OPS, May 22 through All-Star break
Min. 75 plate appearances decided with 2 strikes

1. Yordan Alvarez, HOU: .918
2. Curtis Mead, WSH: .829
3. Geraldo Perdomo, ARI: .825
4. Pete Crow-Armstrong, CHC: .822
5. Bryce Eldridge, SF: .820
6. Juan Soto: .819

But are those numbers enough to convince Soto to stick with the puck knob permanently? The jury is still out.

For one thing, Soto's old bat is tried and true. It gave him eight-plus seasons of being one of the best hitters on Earth. That is not so easily discarded.

Even after Soto had largely switched over to the puck knob bat heading toward the All-Star break, he still flipped back to his old bat at times -- including to hit his dramatic go-ahead three-run homer in the ninth inning off Braves closer Raisel Iglesias on July 6. In a big moment, Soto turned to the classic bat.

"You know, it's the special moments," Soto laughed. "You gotta trust what you have, you know? And that's why I went back to my bat."

He also came out swinging his old bat to start the second half … only to switch back to the puck knob bat for a two-hit game in the series finale against the Phillies … only to use his old bat again during the Mets' current series against the Brewers. Despite promising results, the experiment is clearly not yet complete.

"We haven't come up with all the answers yet, because [the Mets are] still looking at everything, they're trying to make sure they have the right answer for me," Soto said. "So I'm just waiting for that, and we're gonna see if I go back to the puck knob or go to my normal bat."

The whippy swing Soto can generate with the puck handle bat might be good for battling with two strikes, but there is also one significant potential tradeoff in his raw bat speed.

Soto's bat speed did dip for the remainder of the first half after he switched bats. Part of that goes hand in hand with the shortening of his swing -- a shorter swing path means less time for the bat to accelerate to a higher speed. And early on in the second half, as Soto has used his old bat for a few games, his bat speed is back up.

Soto's bat speed after switching to puck knob

• Overall: 72.9 mph --> 71.2 mph
• <2 strikes: 73.9 mph --> 72.0 mph
• 2 strikes: 70.8 mph --> 69.8 mph

Soto's bat speed using his old bat to start the 2nd half

• Overall: 73.1 mph
• <2 strikes: 74.2 mph
• 2 strikes: 72.1 mph

At the end of the day, bat speed matters, and keeping it up is important to Soto.

"We're trying to see," Soto said. "Definitely we want the bat speed, though. So if it's lower we're probably gonna make some adjustments."

How much of that bat speed difference is directly attributable to Soto's physical bat is hard to say. But it does seem like the different styles of bat at least in some way trigger different styles of swing.

It's up to Soto to pick what he wants. But whatever tool of the trade he uses, it's extremely likely that he'll simply continue to be an MVP-caliber hitter.

"I will try to use the [hockey puck] knob," Soto said. "And it just depends. We have enough swings, enough at-bats to actually see if it's helping me or not. I asked the team here -- we have a really good 'Statcast' group here, they do a lot of work -- and we've been asking them if my swing speed has been down, has been up. And we're gonna make a decision."