The names are swirling, and the fate of the respective playoff contenders could be hanging in the balance. Several teams will get one last chance to improve their clubs on Tuesday, when the league's non-waiver Trade Deadline at 4 p.m. ET will pass, making roster movement more difficult.
Teams will still have a chance to make trades in August, but they'll have to pass players through waivers in order to move them. That's why there's such a huge amount of attention paid to Tuesday's Deadline, and it also explains why so many teams have been active in filling their holes in July.
Zack Greinke has already switched addresses, and so has Hanley Ramirez. There are rumors swirling around pitchers like Cliff Lee and Ryan Dempster, two names that could impact the postseason no matter where they wind up. And even if nothing happens Tuesday, it's been a busy trading season.
Rewind back a month ago and you can see how much things have changed. The White Sox acquired Kevin Youkilis from Boston in the last week of June, and the Orioles got veteran Jim Thome from the Phillies the day before July started. And from there, the trading only seemed to intensify.
Take the Marlins, for instance. Miami seemed to be a potential buyer on July 4, when it acquired Carlos Lee from Houston for Matt Dominguez and Robert Rasmussen. Two weeks later, though, Miami had changed tack, electing instead to deal Ramirez, Omar Infante and Anibal Sanchez.
Just like that, the Marlins had traded their third baseman of the present (Ramirez) and future (Dominguez) for a host of arms that could help them compete at some point down the line. The Marlins got Nathan Eovaldi and Scott McGough from the Dodgers in the Ramirez trade, and they wound up with prized right-hander Jacob Turner as the main piece from Detroit in the Infante/Sanchez deal.
And if the Marlins weren't quite sure which direction they should travel, you can credit the Astros for knowing exactly what they were doing. Houston didn't just stop after adding Dominguez -- the 12th overall pick in the 2007 First-Year Player Draft -- but instead completed a few more trades.
Houston caught the attention of the baseball world on July 20, when it cobbled together a 10-player trade that sent veterans Brandon Lyon and J.A. Happ to Toronto. The Astros received Francisco Cordero and Ben Francisco in that trade, but they also got younger, netting pitching prospects Asher Wojciechowski and Joseph Musgrove as well as Minor League catcher Carlos Perez.
The Astros didn't stop there. Houston also sent veteran Brett Myers to the White Sox on July 21 in exchange for prospects Matthew Heidenreich and Blair Walters. And three days after that, Houston traded southpaw Wandy Rodriguez to Pittsburgh for Rudy Owens, Colton Cain and Robbie Grossman.
The Yankees also joined the fray on July 23, acquiring iconic outfielder Ichiro Suzuki from the Mariners for two Minor League right-handers -- D.J. Mitchell and Danny Farquhar -- to fill a hole created by Brett Gardner's injury in left field and in the bottom part of their lineup.
Greinke, the biggest prize on the open market, was acquired by a team that took a risk. The Angels sent three of their best prospects -- athletic shortstop Jean Segura and right-handed pitchers John Hellweg and Ariel Pena -- to Milwaukee, despite Greinke not being signed for next year.
Los Angeles will have a couple of months to entice Greinke to delay his shot at free agency, and it may have to pick up its pace to accomplish that task. The Angels are five games out of the American League West lead heading into Monday night, but they're right in the mix for one of the league's Wild Card slots.
The White Sox were another team that took that path, acquiring Myers and Francisco Liriano to re-arm a team with designs on the postseason. Chicago has engaged in a touch-and-go battle with Detroit at the top of the division, and the additions of Myers and Liriano could prove instrumental in August and September.
And while the White Sox were increasing their depth, the Tigers were making a move of their own. Detroit traded its best pitching prospect -- former first-round draftee Turner -- and two other Minor Leaguers to Miami in exchange for Infante and Sanchez, two veterans with extensive experience.
Infante, a former Tiger who played in the 2006 World Series, will help paper over Detroit's glaring vacancy at second base, while Sanchez, a right-handed starter, will attempt to round out the Tigers' rotation depth. Sanchez, 44-46 for his career, has yet to pitch in the postseason.
Not every July deal was a blockbuster. The Royals and Rockies exchanged disappointing starters -- Jonathan Sanchez and Jeremy Guthrie, respectively -- on July 20, and the D-backs sent Marc Krauss and former first-round draftee Bobby Borchering to Houston for infielder Chris Johnson on Sunday.
Krauss, a former second-round draftee, is batting .283 with a .416 on-base percentage and a .509 slugging mark for Double-A Mobile, giving Houston another potential sleeper. Borchering, meanwhile, has struggled to a .130 average in 77 at-bats in his first exposure to Double-A pitching.
So who else could be moved on Tuesday? The Phillies are reportedly open to moving outfielders Shane Victorino and Hunter Pence, and the Red Sox may be willing to trade Josh Beckett. Another player, San Diego's Chase Headley, has been involved in trade rumors all month.
And that's why July is one of the most interesting junctures of the baseball schedule. Some teams are trying to add talent in order to go for broke, and some are trying to divest themselves of players now in order to improve their future prospects. It will take time to sort out which teams succeeded in their disparate efforts, but there will be even more intrigue Tuesday and after the Deadline passes.
Spencer Fordin is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.