Since Aug. 26, they're 11-2 against the Rangers, Tigers and Rays. In the two series that probably decided the American League West, they mashed the Rangers, winning five of six.
They're leading the Majors in runs this month and have hit 68 home runs in the last 43 games. As for their pitching, only one AL team has a better ERA in September. That one club is Cleveland, which is doing its own sprint toward October, but that's another story.
Unlike last season when the A's won the AL West with a late rush, they surprised almost no one by winning again this season. In the end, they were pretty much what we thought they'd be.
I swore I'd get through this entire column without mentioning the A's have the fourth-lowest payroll in baseball. But it's too important to pass over. To do more with less is a tribute to the genius of A's general manager Billy Beane.
The A's simply aren't capable of doing business the way some other teams do it. Beane is proof that roster construction is an art.
His gift is giving his manager platoon options throughout the lineup and trusting him to come up with combinations that work. Only four A's started more than 109 games. Some of that was because of injuries, but a lot of it was manager Bob Melvin's platoon system.
The A's also have stars. Third baseman Josh Donaldson ought to be on every AL Most Valuable Player ballot. That he was left off the AL All-Star team was so silly that it was almost bizarre.
And to think that two years ago he was a catcher. In this, his first full season as an everyday third baseman, he has 24 homers, 37 doubles and a .388 on-base percentage. His defense at third has been terrific.
If things work out just so, the entire country may find out how good he is as the A's wind through this postseason.
Coco Crisp, Brandon Moss and Yoenis Cespedes all have at least 22 home runs. Overall, the A's are third in the AL in runs, third in home runs, second in doubles and fourth on OPS.
To sum up, this lineup is as good as any in baseball except perhaps that of the Red Sox. But pitching is the A's strength. Beane has done a fabulous job collecting arms, and the A's starters have the second-best ERA in the AL. Meanwhile, their bullpen has the third-best ERA.
Their rotation begins with 40-year-old Bartolo Colon, but there's depth and quality -- A.J. Griffin, Jarrod Parker and rookies Dan Straily and Sonny Gray -- behind him.
There's something else about these A's that's special. It's something that's hard to define for those of us on the outside, but it's one of the strengths of the club. That is, players love playing for the A's. That has been true for most of the last 20 years and remains so today.
There's a looseness in the clubhouse, a group of players who have fun and enjoy and respect one another. Some of that is having people like closer Grant Balfour and Donaldson, who are smart and funny and seem to be having the time of their lives.
Some of it is Melvin. He's one of those rare people who is so decent and so likable that players want to play for him. He's got a tough side and is not to be crossed. Just ask some of the umpires who have been on the wrong side of his temper.
But Melvin's magic -- and Beane is part of this -- is getting players to buy in. To play for the A's is to understand that your playing time is not guaranteed. In the end, though, Melvin is going to do what he believes is best for the team, and every player seems to quickly understand.
And maybe because so many players are used, maybe because there's still plenty of youth on the club, the A's are all in. The Red Sox probably begin these playoffs as the consensus pick to win the AL pennant, but the A's would surprise almost no one by winning a championship.
This division championship lacked the drama of last season when they spent exactly one day in first place. That one day happened to be the only one that mattered -- after the 162nd game -- but still. These A's have a week to gather themselves and to refocus. Don't overlook them.
Richard Justice is a columnist for MLB.com. Read his blog, Justice4U.