It's the end and the beginning. It's a time for joyful celebration and of heartbroken closure. It's Must-Win Week, and it's one of the most exciting seven-day periods in baseball.
Must-Win Week marks the transition from September to October, a literal and figurative shift from the 162 games that got us here to the month that brings it all to a championship conclusion.
Must-Win Week brings us mathematical certainty, statistical finality and momentum that carries into October and beyond.
Not much is unknown as the week arrives, but there are still five intriguing questions to be answered over the next seven days, and No. 1 starts in Pittsburgh.
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1. Can the Pirates catch the Cardinals in the National League Central?
Technically, they can, and it's still a tall order, but it's not as tall as it used to be. And look at the next date for the two teams: three games beginning Monday night in PNC Park as Must-Win Week begins in earnest.
Pittsburgh lost to the Cubs on Sunday night, 4-0, but the team won its previous eight games before that. The Cardinals lost, 8-4, to Milwaukee on Sunday, so the Pirates are now only three games behind St. Louis in the NL Central with six to play. The week begins with the Cardinals, who last week lost breakout star starter Carlos Martinez (shoulder) for the season, playing three games against the Pirates in Pittsburgh.
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If the Pirates sweep, the division would be tied and the Bucs would rate a slight edge to take it over the weekend, with the rest of their games at home against Cincinnati while St. Louis has to finish off vs. the Braves in Atlanta.
"No doubt, everybody who plays the game wants to play their best baseball at the end," Pirates manager Clint Hurdle said. "We've obviously picked up momentum across the board. We've been been playing our best baseball."
2. Kansas City or Toronto for home sweet home?
For a large part of the season, it appeared that the Royals had a hammerlock on home-field advantage throughout the AL postseason. But then the Blue Jays' second-half surge happened, and with one week remaining in the regular season, the teams have identical records. If they both finish the 162-game grind with the same marks, Toronto would get the nod because the Jays won the season series between the two clubs, 4-3.
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Interestingly enough, both teams will not play another regular-season game at home. The Jays will play four against the Orioles in Baltimore and three at Tampa Bay.
Meanwhile, the Royals will take part in a very interesting Monday game when they hit Wrigley Field for a rainout makeup date against the Cubs before they play the White Sox on the South Side for three.
Monday's game not only features two possible World Series combatants. It's also a spin of sorts on the events of last year, when the Royals hosted the AL Wild Card game and had to overome then-A's pitcher Jon Lester, who's now a clubhouse leader for the Cubs, the likely visiting team in this year's NL Wild Card game.
There's always a fine line between resting up the roster prior to the postseason and going all-out until Game No. 162. We'll see how the Royals and Blue Jays handle it, and we'll see who comes out with home field.
3. Do the defending champs have a glimmer of hope?
Mathematically, yes, but that hope is barely alive. At least the San Francisco Giants, winners of the last three World Series titles in even years, can make up a lot of ground very quickly when they open Must-Win Week with the team ahead of them in the NL West, the Dodgers.
San Francisco hosts Los Angeles for four games, and the Giants literally must win all four to prevent elimination. They can't even ponder the later part of the week because the Dodgers will clinch the NL West with a single victory and the Giants have already been knocked out of Wild Card contention.
The Dodgers, of course, would seem to have bigger goals in mind, since they're now 1 ½ games behind the Mets in the race for home-field advantage for their probable NL Division Series matchup.
"The best thing about where we're at is we don't have to look or think about the scoreboard," Dodgers manager Don Mattingly said Sunday of his club's win-and-you're-in status. "We can't be in a much better situation than we're in right now. A lot of teams would trade spots with us."
4. Can the Astros catch the Rangers in the American League West?
Yes, but it'll be tough. Houston helped itself out quite a bit by beating Texas on Saturday, 9-7, and Sunday, 4-2, and now the Astros enter the week with a deficit of 2 1/2 games. But the Rangers still have that 2 1/2-game cushion, and they have the easier remaining seven games on the schedule.
Texas is at home for all seven, with three games at Globe Life Park against the Tigers followed by the season-ending four-game set against the very-much-alive Angels. The Astros have to venture out on the road for all six games: three against the Mariners in Seattle and three against the D-backs in Phoenix. And the Astros to this point have the worst road record in the AL at 29-46.
5. Who will win the final AL Wild Card spot?
OK, the topic begins with the Astros … again. Houston remains a half-game up in the AL Wild Card standings despite all their recent struggles, and that weekend of winning against the Rangers helped. So it seems a tad unlikely that they'll catch the Rangers for the division, and if they don't, they're hardly a shoo-in for the Wild Card.
The Angels, after all, won another close game on Sunday, 3-2, against the Mariners to stay right behind Houston, and the Angels get three home games against the last-place A's to begin the week. Then, they get the tough task of four games on the road against Texas, but the standings could be altered rather radically by the time the team sets foot in Arlington. Add to that the fact that Mike Scioscia's club has likely lost closer Huston Street for the season with what the Scioscia called a Grade 1 groin strain and things are even more up in the air.
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Then, there are the Twins. Minnesota handled Detroit on Sunday, 7-1, and the club is now 80-75 -- one game from guaranteeing at least a .500 record in a resurgent season. The Twins are also a mere 1 1/2 games behind Houston in the Wild Card race. That's quite an achievement for first-year manager Paul Molitor, but they're looking for even more.
They'll get a stern test in Must-Win Week with four games against the not-quite-out-of-it-yet-either Indians (four games out of a Wild Card spot entering the week) at Cleveland in the early part of the week. Then they will host AL Central champs Kansas City for the final three games.
They don't call it Must-Win Week for nothing.
Doug Miller is a reporter for MLB.com. Follow him on Twitter @DougMillerMLB.