Here's a look at the best free-agent signings for each team this century. Some of these players are still on the team, some of them provided their teams tons of value in the past, some of them are just getting warmed up.
Note: For each player, the year listed is the first season he played with the club after he signed the contract, even if he actually signed it the previous November or December.
Blue Jays: Russell Martin, five years, $82 million, 2015
Martin was perfect fit for a Blue Jays team that leaped when its window was open and made it to the American League Championship Series in consecutive years, with Martin playing a big part.
Orioles: Wei-Yin Chen, three years, $11.3 million, 2012
Chen was perhaps the Orioles' most consistent pitcher for his four years in Baltimore (the club picked up an option for a fourth season), and Miami rewarded him with an even bigger contract when he left.
Rays: Carlos Pena, Minor League deal, 2007
Pena hit 46 homers for the Rays that year, and he was just as good when they re-signed him to a three-year, $24 million deal the next season -- the year Tampa Bay went to its lone World Series.
Red Sox: David Ortiz, one year, $1.25 million, 2003
Ortiz was only a free agent because the Twins released him, making this arguably the most fortuitous free-agent signing ever. Every contract the Red Sox signed him to after this one -- for much more money than he got in this deal -- was more than worth it for them as well.
Yankees: Hideki Matsui, three years, $21 million, 2003
"Godzilla" hit a total of 70 homers across the three-year span of his original deal with the Yankees. He'd later re-sign for four years, ending his career in New York by being named World Series MVP in 2009.
Indians: Juan Gonzalez, one year, $10 million, 2001
This was JuanGone's last full season, and he finished fifth in MVP voting before returning to Texas for the declining years of his career.
Royals: Edinson Vólquez, two years, $20 million, 2015
Kendrys Morales was another option here, as both helped the Royals win that elusive World Series.
Tigers: Ivan Rodriguez, four years, $40 million, 2004
Both the Tigers and Rodriguez were widely criticized when he signed such a big deal with one of the worst teams in baseball. Two years later, they were both in the World Series.
Twins: Jim Thome, one year, $1.5 million, 2010
He came back for $3 million the next season, but he was outstanding in 2010, helping the team to the playoffs and looking like a natural fit in a Twins uniform.
White Sox: Jermaine Dye, two years, $10.15 million, 2005
Dye was the slugger the White Sox needed, and by the end of the deal, he had won a World Series MVP Award.
Angels: Vladimir Guerrero, five years, $70 million, 2004
This Hall of Famer's contract, which came a couple of years after A-Rod signed for $252 million with Texas and Manny Ramirez signed for $160 million with Boston, looked like a bargain by comparison.
Astros: Roger Clemens, one year, $5 million, 2004
Clemens signed roughly the same deal with the Astros in 2005, which, according to ERA+, is the best year of his career.
Athletics: Bartolo Colon, one year, $3 million, 2013
Colon was 40 in 2013, when he put up the lowest ERA of his career (2.65).
Mariners: Ichiro Suzuki, three years, $14 million, 2001
Technically, Ichiro was signed last century, but since he didn't play his first game until this one, we're counting him.
Rangers: Adrián Beltré, five years, $80 million, 2011
Beltré had just rebuilt his value in Boston on a one-year deal after a tumultuous five years in Seattle, and went on to become a legend in Texas and cementing his status as a future Hall of Famer.
Braves: Billy Wagner, one year, $7 million, 2010
Wagner's lowest ERA of his career (1.43) came in his final season, which he played in Atlanta.
Marlins: Ivan Rodriguez, one year, $10 million, 2003
Yep, Pudge is on here twice, and why not? He was the vocal leader of a World Series-winning team.
Mets: Carlos Beltrán, seven years, $119 million, 2005
The only people not convinced of this are, of course, Mets fans. Per Baseball Reference's WAR, his two best seasons (and three of his best five) came in Queens.
Nationals: Max Scherzer, seven years, $210 million, 2015
Many teams were scared off by Scherzer's age and violent delivery. Suffice it to say, he proved naysayers wrong during this contract.
Phillies: Cliff Lee, five years, $120 million, 2011
People were scared off by Lee as well. But he was fantastic nearly every year he was in Philadelphia.
Brewers: Lorenzo Cain, five years, $80 million, 2018
The Brewers have made the postseason every year since Cain signed this contract, and the center fielder has produced 12.0 bWAR over 372 games with the club.
Cardinals: Matt Holliday, seven years, $120 million, 2010
The Cardinals parted ways with Holliday at the end of his deal, but he provided excess value to them essentially every year of the contract.
Cubs: Jon Lester, six years, $155 million, 2015
Lester posted a 3.64 ERA over 171 regular-season starts and a 2.44 ERA across 12 postseason appearances for the Cubs and helped bring home the franchise's first World Series title since 1908.
Pirates: Russell Martin, two years, $17 million, 2013
The Pirates' postseason breakthrough happened the second year of this contract, and Martin was instrumental in making that happen. (Fun note: There are two guys featured twice in this piece, and both of them are catchers -- Martin and Pudge.)
Reds: Aroldis Chapman, six years, $30 million, 2010
Say what you will about the Reds, but they were in on Chapman first.
D-backs: Randy Johnson, four years, $52 million, 1999
The easiest pick on this whole list, obviously. Johnson won the NL Cy Young Award every single year of this deal, going a combined 81-27 with a 2.48 ERA and 1,417 strikeouts in 1,030 innings.
Dodgers: Derek Lowe, four years, $36 million, 2005
The veteran right-hander won 54 games for the Dodgers between 2005-08, never starting fewer than 32 games in a season during that stretch. Yasiel Puig also has a case.
Giants: Ray Durham, three years, $20 million, 2003
Durham hit .286/.362/.451 during this deal, helping the Giants win 100 games in his first year in San Francisco. Barry Bonds would, of course, be the all-time answer, but the only free-agent deal he ever signed with the Giants came prior to the 1993 season, precluding him from qualifying here.
Padres: Joaquin Benoit, two years, $15 million, 2014
Benoit had been a closer the previous year for the Tigers, but the Padres used him as an all-purpose reliever, and he put up a 1.96 ERA over his two seasons in San Diego.
Rockies: Mark Reynolds, one year, $1.5 million, 2017
Reynolds signed a one-year deal with Colorado prior to the 2016 season and was serviceable. He then signed another one-year deal for the following season for less money, and the Rockies got 30 homers out of him on the way to earning a Wild Card spot.