Jason O. Watson/Getty Images

The Oakland Athletics snuck up on us, the same way Matt Chapman sneaks up on a speedster who thinks he can drop a bunt down the third-base line and come up with a hit. Sorry, Dee Gordon, Jarrod Dyson or anyone else whom Chapman has robbed this year.

The A's are pounding their way into our consciousness, the way their young third baseman has singled and doubled and homered his way into the national baseball conversation.

If you're not paying attention to Chapman and the A's, well, you should be. If you're not making plans to check out their series this week against the Los Angeles Dodgers, or next week's playoff-race showdowns with the Seattle Mariners and Houston Astros, well, go ahead and change your plans.

As hot as the Boston Red Sox have been since the middle of June, the A's have been just a tiny bit hotter. That's not to say the A's are as good a team as the Sox, who seem on their way to one of those historic seasons. But by the middle of June, we already knew the Red Sox were good.

In the middle of June, the A's were a sub-.500 team you almost felt sorry for because the lack of commitment by ownership was showing in their on-field performance. No team in the major leagues had a lower Opening Day payroll than the A's, whose $62 million total was less than a third of the Red Sox's $206 million, according to USA Today.

Then the A's started winning. And kept winning.

They've won 33 of their last 43, the best record in baseball over that span (the Red Sox are just behind at 31-11). They've gone from 11 games out of a playoff spot to holding the American League's second wild-card spot. They're just 2.5 games behind the New York Yankees for the right to host the AL Wild Card Game and just four games behind the Astros in the AL West.

You can't credit Chapman for all that, because he was on the disabled list for two weeks with a thumb contusion when the run began. But he's important enough that one person who works for the A's described him as "captain material," even though he's just 25 and in his first full big league season.

Jason O. Watson/Getty Images

His numbers are good enough that you wonder why he wasn't on the All-Star team, except that the AL had two really good third basemen in Jose Ramirez and Alex Bregman, and Chapman's numbers were behind theirs when the team was picked.

But look at him now: A 1.214 OPS in 16 games since the All-Star break, second in the AL among players with at least 60 plate appearances (Rougned Odor of the Texas Rangers is first). A triple and two home runs over the weekend as the A's swept the Detroit Tigers to continue their run.

Then there are the defensive numbers. Defensive stats aren't the most reliable indicators, but in Chapman's case, he's so far ahead of everyone else the numbers don't need to be exact. Check out this tweet from Sports Info Solutions:

Even if you don't trust defensive numbers, in Chapman's case, the eye test tells you the same thing.

"A Gold Glove guy at third base," one American League scout said Monday. "A smart player and a great athlete with a plus-plus arm. One of the best, for sure."

Or listen to this testimonial from Nolan Arenado of the Colorado Rockies, who has been considered the best defensive third baseman in the game.

"He was my backup shortstop [in high school]," Arenado told Susan Slusser of the San Francisco Chronicle. "It's funny, he's probably better than me now."

Stacy Revere/Getty Images

So yeah, the two guys who might be the best defensive third basemen in the game played together at El Toro High School in Orange County, California. It's kind of like how Didi Gregorius rarely played shortstop growing up because he and Andrelton Simmons were on the same teams back to Little League.

For the record, Chapman told Slusser he still rates Arenado as better.

"I want to do what he's done," Chapman said.

Arenado has won the National League Gold Glove at third base in each of his first five big league seasons. Chapman didn't debut until June in 2017, when Evan Longoria won the AL Gold Glove at third. Longoria isn't even in the league anymore after a December trade to the San Francisco Giants, and it's hard to see anyone denying Chapman this year.

The competition to make the AL All-Star team at third base will be tough with Ramirez and Bregman, but it's easy to see Chapman joining that conversation in the years to come, too.

"He has a Robin Ventura-type mentality," another AL scout said. "Plays the game the way it was meant to be played. I think the offensive numbers will go up. He's an All-Star in the making, for sure."

He's the kind of player you make plans to watch, just as his A's are right now the type of team you should make plans to see.

Danny Knobler covers Major League Baseball as a national columnist for Bleacher Report.

Follow Danny on Twitter and talk baseball.