So after all the comings and goings, which bullpen is best suited for postseason baseball? Raise your hand if you're ready to see October dominated by some new names.
Corey Knebel and Jacob Barnes are doing great work for the Brewers. Tyler Olson is quickly making a name for himself with the Indians. And then there's Brandon Kintzler, who's helping with a transformation of the Nationals' bullpen.
Speaking of the Nats, they've gotten way better in the past month. Before general manager Mike Rizzo made a pair of trades, they'd lost six games in which they had ninth-inning leads. Since then? Zero.
As for the Dodgers and Red Sox, they've been solid almost from the start. Others? The Indians need to get Andrew Miller healthy for the postseason, while the Yankees are hoping Aroldis Chapman can get things figured out.
October is for bullpens. That was true when the Giants rode a tremendous bullpen to three World Series championships in five seasons and even more true when the Royals constructed a super bullpen for their 2015 World Series victory.
Suddenly, the competition is not to acquire one or two quality relievers, but to get as many as possible. Baseball people marveled last season when Indians manager Terry Francona made Miller, a Deadline acquisition, into a devastating multi-inning weapon.
That's why every team spent last offseason looking for its own version of Miller. Problem is, his makeup and talent make him unique.
Great bullpens do not necessarily mean the difference between winning and losing. But they're a more significant step in that direction than ever before. So let's look at 10 teams with a bullpen built for October:
Season: 1.08 WHIP (first), .632 OPS (second), 2.97 ERA (second)
Since Trade Deadline: 1.14 WHIP (tied for eighth), .694 OPS (13th), 3.70 ERA (12th)
Acquisitions: LHPs Tony Watson and Tony Cingrani
Start with the National League's best closer, Kenley Jansen. Throw in an array of dominant setup men in Pedro Baez, Brandon Morrow and Luis Avilan. Mix in the new left-handers. For the postseason, some of the team's rotation depth could manifest itself in a deeper bullpen. Nothing is guaranteed, but the Dodgers simply could not have positioned themselves better.
Video: LAD@PIT: Dodgers 'pen blanks Bucs to seven scoreless
Season: 1.17 WHIP (tied for second), .651 OPS (third), 2.95 ERA (first)
Since Trade Deadline: 1.22 WHIP (11th), .691 OPS (12th), 3.99 ERA (15th)
Acquistion: RHP Joe Smith
Both late men, Bryan Shaw and Cody Allen, have struggled some lately, but lefty Olson hasn't allowed a run in 12 appearances since being called up. But Miller is back on the 10-day DL with right knee soreness. If he's at full strength by the postseason, the Indians should be in business again.
3. Red Sox
Season: 1.17 WHIP (tied for second), .655 OPS (fourth), 3.07 ERA (third)
Since Trade Deadline: 1.14 WHIP (seventh), .684 OPS (10th), 3.25 ERA (ninth)
Acquistion: RHP Addison Reed
In Brandon Workman, Reed and Heath Hembree, manager John Farrell should be able to get the ball to closer Craig Kimbrel even with one of his setup men, Matt Barnes, on the 10-day DL. Joe Kelly's struggles are a source of concern, but the Red Sox are so good and so deep, it might not matter.
Video: NYY@BOS: Kimbrel fans Hicks to end the game
Season: 1.36 WHIP (19th), .763 OPS (28th), 4.68 ERA (28th)
Since Trade Deadline: 0.99 WHIP (third), .559 OPS (second), 2.87 ERA (sixth)
Acquistions: LHP Sean Doolittle and RHPs Ryan Madson and Kintzler
This has been an amazing transformation, from one of the worst bullpens to arguably the best. The Nationals were not good enough to win the World Series before Rizzo acquired the three relievers. Now they are. Even with Madson on the DL with a right finger sprain, the newcomers have allowed the holdovers to slide into more comfortable roles.
Season: 1.18 WHIP (fourth), .680 OPS (sixth), 3.75 ERA (sixth)
Since Trade Deadline: 1.06 WHIP (fourth), .622 OPS (fifth), 2.20 ERA (third)
Acquistions: No relievers
Angels manager Mike Scioscia has made it work despite using 27 pitchers. Cam Bedrosian, Blake Parker, Eduardo Paredes and Yusmeiro Petit aren't big names, but their work has been terrific. Bud Norris, a February signee with his sixth organization, has done mostly solid work in the closer's role.
Video: LAA@BAL: Norris retries Beckham to solidify the save
Season: 1.19 WHIP (fifth), .626 OPS (first), 3.35 ERA (fourth)
Since Trade Deadline: 1.08 WHIP (fifth), .603 OPS (fourth), 3.34 ERA (10th)
Acquistions: RHPs David Robertson and Tommy Kahnle
The Yankees still have a dominant bullpen, even with Chapman struggling and having been removed from the closer's role. Dellin Betances and Robertson have combined for 19 scoreless innings since the Trade Deadline, and Adam Warren continues to do great work. If Chapman gets back on track, this could be baseball's best 'pen.
Season: 1.24 WHIP (sixth), .701 OPS (eighth), 4.12 ERA (15th)
Since Trade Deadline: 1.28 WHIP (13th), .656 OPS (eighth), 1.73 ERA (first)
Acquisitions: LHP Francisco Liriano, RHP Tyler Clippard
Houston's most significant addition has been the emergence of former starter Joe Musgrove as a lockdown reliever (nine appearances, 0.63 ERA). Musgrove's important addition at a time when one setup man, Will Harris, was injured, and another, Chris Devenski, was struggling. The Astros envision a postseason in which they'll have Harris, Devenski, Musgrove and Luke Gregerson lined up in front of closer Ken Giles. That group could be as good as any.
Season: 1.32 WHIP (13th), .742 OPS (18th), 3.81 ERA (seventh)
Since Trade Deadline: 1.14 WHIP (tied for eighth), .652 OPS (seventh), 2.74 ERA (fifth)
Acquisition: No relievers
First, the Orioles have one of baseball's two best closers in Zach Britton. Second, the O's have a manager, Buck Showalter, who manages a bullpen better than almost anyone. Darren O'Day is a dominant setup man, while Richard Bleier, Miguel Castro and Mychal Givens have been very good.
Video: DET@BAL: Britton strikes out Hicks to earn the save
Season: 1.34 WHIP (15th), .762 OPS (27th), 4.53 ERA (23rd)
Since Trade Deadline: 0.81 WHIP (first), .570 OPS (third), 3.05 ERA (eighth)
Acquistions: No relievers
Despite trading Kintzler to the Nationals, the Twins have climbed back in contention, in part thanks to solid bullpen work. Four relievers have recorded a save over the past three weeks. There are no big names, but Ryan Pressly, Alan Busenitz, Trevor Hildenberger, Tyler Duffey and Taylor Rogers all have ERAs under or close to 2.00.
Season: 1.44 WHIP (27th), .760 OPS (26th), 4.01 ERA (11th)
Since Trade Deadline: 1.36 WHIP (19th), .673 OPS (ninth), 1.75 ERA (second)
Acquistions: RHPs Anthony Swarzak and Jeremy Jeffress
Knebel has emerged as one of the best closers in the game, and Swarzak has slid nicely into the eighth-inning role. Manager Craig Counsell has done great work lining up the others -- Barnes, Jared Hughes, etc. -- in front of them.
Richard Justice has been a reporter for MLB.com since 2011. Read his columns and follow him on Twitter at @RichardJustice.