It's hard to fake your way through 162 games, so most MLB playoff teams have earned the right to play in October. Once every few years, a team in a weak division slips into the playoffs with a mediocre record, but teams like the 2005 Padres and 2006 Cardinals are exceptions.
Now that this year's postseason lineup has been determined, we have the chance to look back at the trades the eight playoff teams made this year. Here's a summary of the in-season acquisitions that made an impact for one of MLB's 2011 playoff teams (linked team names go to our Transaction Tracker):
- Phillies: Hunter Pence, John Bowker
- Cardinals: Rafael Furcal, Edwin Jackson, Marc Rzepczynski, Octavio Dotel, Corey Patterson
- Diamondbacks: Jason Marquis, Brad Ziegler, John McDonald, Aaron Hill
- Brewers: Nyjer Morgan, Sergio Mitre, Francisco Rodriguez, Felipe Lopez, Jerry Hairston Jr.
- Yankees: Sergio Mitre
- Rays: None
- Tigers: Wilson Betemit, Doug Fister, David Pauley, Delmon Young
- Rangers: Koji Uehara, Mike Adams, Mike Gonzalez, Matt Treanor
All four National League teams added valuable contributors in midsummer trades. The Rangers improved their bullpen with a pair of highly-coveted late-inning relievers and the Tigers acquired Doug Fister, who posted a 1.79 ERA with a 57K/5BB ratio in 70 1/3 innings down the stretch and is arguably the acquisition of the season.
After months of rumors about the Yankees' interest in starting pitching, GM Brian Cashman remained quiet on the trade front. The Wild Card Rays were also inactive despite constant rumors about B.J. Upton, James Shields, Johnny Damon and others. Tampa Bay's midseason acquisitions came from the minor leagues, where Desmond Jennings and Matt Moore began the season.
The Yankees and Rays are not averse to trading players – Cashman nearly acquired Cliff Lee last summer and Friedman makes major trades just about every year. Similarly, the Tigers and Brewers aren't this aggressive every year – they simply saw potential upgrades on the market. If there's a lesson here it's that the significance of the trade market varies wildly from year to year and from team to team.