Nearly a billion dollars across 112 contract years was committed to 33 players with less than six years of Major League service time during the 2009-10 offseason extension period, spanning October 2009 through April 2010.  Joe Mauer, Ryan Howard, Justin Verlander, Felix Hernandez, and Justin Upton each signed deals worth at least $50MM.  Two years removed from this extension period, which contracts now appear the most regrettable?

• Howard's five-year, $125MM extension begins with the 2012 season, the beginning of which he'll miss due to a torn Achilles tendon.  Ruben Amaro's deal was panned at the time and only looks worse now.
• Mauer's eight-year, $184MM extension began with a whimper, as he was limited to only 82 games and showed no power at the plate in 2011.  Bill Smith technically gets credit for this one, but any $100MM+ deal goes beyond the GM level.
• Amaro signed Joe Blanton to a three-year, $24MM deal prior to the 2010 season.  Due to an elbow injury, Blanton didn't provide his usual innings in 2011.  He's penciled into the 2012 rotation to finish off the contract.  The main player the Athletics received for Blanton in '08 was Adrian Cardenas, who was recently designated for assignment.
• Rockies GM Dan O'Dowd signed Huston Street to a three-year, $22.5MM deal two years ago.  Street was decent for 105 2/3 innings for the 2010-11 Rockies, but they unloaded him to San Diego last month in a salary dump.  It seems the Rockies decided Rafael Betancourt could handle the ninth inning at setup man-type money.
• Mariners GM Jack Zduriencik locked up center fielder Franklin Gutierrez to a four-year, $20.5MM deal.  At the time, locking down the arbitration years of a defensive-minded player did not seem necessary, since the arbitration process rewards power numbers for position players.  The Mariners still may benefit from getting one or two of Gutierrez's free agent years, if he bounces back.
• Adam Lind's extension was the first authored by GM Alex Anthopoulos, and the initial returns are ugly.  It's a team-friendly deal with steady arbitration salaries and three club options, but the bottom line is the team guaranteed $18MM to a player who may not have a future as a regular.
• Mark Reynolds' three-year, $14.5MM extension was a Josh Byrnes deal.  Home runs pay in arbitration and defense may be largely ignored, but a .210 batting average affects earnings negatively.  Since the contract only covered arbitration years, it was probably best to just let the process play out.
• In addition to Mauer, then-Twins GM Bill Smith locked up starter Nick Blackburn for four years and $14MM, plus a club option.  Like many of the players on this list, Blackburn may have seemed at the time like a nice guy to have around, but going year-to-year made more sense.
• As a non-tender candidate with the Royals, Mark Teahen's three-year, $14MM extension from White Sox GM Kenny Williams was surprising from day one.  The Blue Jays took him off their hands to facilitate the Edwin Jackson deal that led to their Colby Rasmus acquisition, and will pay Teahen $5.5MM to not play for them in 2012.
• Athletics GM Billy Beane guaranteed $12.5MM to Brett Anderson, at the time a record for a pitcher with less than two years of service.  Because of Anderson's elbow issues and eventual Tommy John surgery, it turns out guaranteeing him at least $8.5MM for his first two arbitration years was a mistake.  The club option on Anderson's first free agent year (2015) might still be a plus, but they'd have to overpay at $8MM for his third arbitration year in 2014 to have the chance to realize that.
• Rangers GM Jon Daniels rewarded Scott Feldman with a two-year, $11.5MM deal, covering the pitcher's last two arbitration years.  I suppose the main benefit was a $9.25MM option on the righty's first free agent year, but that's not looking valuable now.
• There are a few more multiyear extensions from the 2009-10 offseason worth less than $10MM that proved unnecessary.  The overall point is that teams often don't win by guaranteeing multiyear earnings of arbitration eligible players.  To evaluate extensions this winter, one must estimate the amount of the arbitration savings compared to going year-to-year, and also determine the value of potential free agent seasons.  For non-stars or players with one good year under their belts, year-to-year is usually the way to go.  
• Perhaps the Mauer and Howard contracts demonstrate that letting a star reach or finish his contract year has its benefits, even if it increases the risk of losing the player to free agency.  On the other hand, Justin Verlander and Felix Hernandez both currently have three-year commitments worth $60MM or less with their original teams, as opposed to seven or eight-year free agent deals signed this winter in excess of $160MM.

Jorge Posada, Orlando Cabrera, Craig Counsell, and Adam Everett retired this offseason, as MLBTR's free agent tracker shows.  Which other unsigned free agents may be leaning toward calling it a career?

• Milton Bradley: The Mariners released him on May 16th, and we haven't heard anything since aside from off-the-field issues.  I've heard that while he has not retired, as of now it does not look like Bradley will play in 2012.
• J.D. Drew: About a week ago, Jon Heyman wrote that Drew is "very likely to retire."
• Jason Kendall: In July, we learned that Kendall was out of the picture for 2012 after re-tearing two tendons in his right rotator cuff.  Kendall's career might be over, wrote Nick Cafardo of the Boston Globe at the time.
• Derrek Lee: This month Joel Sherman of the New York Post suggested a kind of "forced retirement" is possible for Lee, who has reportedly been picky so far this offseason.
• Jason Varitek: The catcher is mulling retirement, wrote Scott Lauber of the Boston Herald this month.
• Javier Vazquez: Reports this month continue to indicate that Vazquez will retire.  The 35-year-old would be finishing on a high note.
• Tim Wakefield: He told John A. Torres of Florida Today that retirement is possible, though the knuckleballer hopes to return to the Red Sox.

Contract extensions, especially for arbitration eligible players, are all about comparables.  Position and service time are a couple of major factors for which players are often compared.  This kind of research was previously a tall order for those not employed by a team or agency, but MLBTR's new extension tracker removes the hassle.

The extension tracker shows all contract extensions, whether they cover the player's arbitration years, free agent years, or both.   All the extensions are listed by date, and our filter button allows you to change the date range.  You can also filter by any combination of team, position, guaranteed years, amount in millions, number of options, service time, super two status, and agency.  The service time filtering allows you to choose one or both boundaries of a range.  Service time is denoted as years.days, so 4.148 means four years and 148 days.  A full year of service is 172 days.  The player name is hyperlinked to MLBTR's post on the story of the extension.

Please note that some of the data prior to 2011 is still in the process of being added, such as service time, position, and number of options.

The extension tracker can be found under the Tools menu in the navigation bar up top, along with our 2012 free agent tracker, arbitration tracker, agency database,  transaction tracker, and other features.