There's a tension that simply isn't there during the first five months of a regular season. During the playoffs, everything is cranked up even more. Pressure becomes a daily part of the lives of players, coaches and managers.
Skippers know that every decision could be the one that ends a season. Players feel that way about each and every at-bat.
And then when it ends, no matter how it ends, players experience a range of emotions. Mostly, though, they're more tired than they ever imagined being.
Players describe it as being the best thing they ever experience and also one of the most draining.
"Really, it's why we play," Andy Pettitte said.
It's also the thing players miss most when their careers end. It's not the games as much as the feeling of being part of a team and working for eight or nine months to achieve a goal.
Along the way, teams are pulled this way and that way. There's disappointment and injury, happy nights and angry nights -- a whole range of things.
But the really good teams are made up of a bunch of guys who never lose sight of the prize.
So here we are halfway through September, down to fewer than 20 games, down to that point where slumps are magnified and heroes are born.
"It's funny how these games seem more important, because it's down to the wire," Phillies left-hander Cliff Lee said.
He made the point that the good teams play the same way from the beginning of the season until the last day.
If some people think a few games at the end are more important than those at the beginning, they may not understand the mentality of the game's best players.
Regardless, we're at the point where some teams are hanging by a thread and others are still trying to position themselves for October.
With 18 of baseball's 30 teams within 5 1/2 games of a playoff berth, with the National League Wild Card race now bordering on ridiculous, this weekend's schedule includes some series that may go a long way toward deciding playoff berths.
Rays at Yankees
The Rays are four games out of both the division and Wild Card races after being swept in a three-game series in Baltimore, including the final two on walk-off singles. They lost three full games in the standings and are in close to a must-win situation beginning Friday. The Rays were 5 1/2 games out at this point last season, so they've been down this road before.
The Yankees remain tied with the Orioles in the American League East despite winning consecutive games for the first time since Aug. 14-15. Friday's game is especially important for CC Sabathia. Manager Joe Girardi was peppered with questions about him last weekend after another lackluster start against the Orioles. With Ivan Nova back from the disabled list and Pettitte about to return, the Yankees are feeling good about things. But they also need Sabathia performing at a high level.
Orioles and A's
This series features baseball's two most surprising, two most amazing teams. Neither was expected to contend. The A's have soared back into contention with rookie pitchers getting 42 of their 82 victories and an offense built around home runs. No, this isn't your father's Moneyball formula.
Meanwhile, the Orioles have ridden manager Buck Showalter's brilliance and general manager Dan Duquette's shrewd personnel moves to their first winning season in 15 years. Tons of credit should go to the core guys in the clubhouse: Adam Jones, Matt Wieters, Nick Markakis and Jim Johnson.
The A's have the AL Wild Card lead, but are just three behind the Rangers in the AL West. The Orioles began the day tied for the Yankees in the AL East and leading the race for the second Wild Card berth.
Cardinals at Dodgers
Both teams have had bad months. The Dodgers have scored the fewest runs in the Major Leagues, while the Cardinals have dealt with an assortment of problems. Regardless, both teams are still in contention and control their destiny. The Cardinals hope to get Chris Carpenter back in the rotation next week, and the Dodgers cling to the belief that Matt Kemp, Adrian Gonzalez and Hanley Ramirez are more than due to snap out of their September slumps.
Beyond the series that feature contenders going at one another, there are teams that need to win to keep stay in contention. The Phillies and Brewers have gotten themselves back in contention, but every loss at this point would be critical. That's also true for the D-backs and Tigers and others. In short, it's September baseball at its best.