With 30 Major League teams, there are hundreds of possible combinations of trade partners, and every one has come to fruition at least once since MLB expanded to 30 teams for the 1998 season.

But some of these pairings are much rarer than others, and many haven’t been seen for a decade or longer. In fact, Baseball Reference’s franchise trade history tool provides a way to see each team’s most long-lost trade partner.

For some teams, their most extensive active drought is with either a current division opponent or a team that shares the same market, perhaps suggesting a reticence to deal with a club that could frequently remind them of a mistake. Others are more surprising, though whether they’re due to front-office dynamics -- in some cases overlapping multiple regimes -- or simple chance, it’s difficult to say.

Here is a look at which trade partner has eluded each of the 30 clubs for the longest, working up toward the longest active drought. Each is listed with the date and details of the last swap between the two parties.

Athletics: Indians (Aug. 31, 2016)
Acquired Colt Hynes for Coco Crisp and cash

Playing in his final MLB season, Crisp went on to hit .269 with two homers and a .922 OPS over 12 postseason games for a Cleveland team that won the AL pennant. Hynes didn't appear in MLB after this trade.

Blue Jays: White Sox (Aug. 26, 2016)
Acquired Dioner Navarro for Colten Turner

Talk about working the room. Ross Atkins took over as the Blue Jays’ executive vice president of baseball operations and general manager in December 2015, and in five years since then, he has already hashed out a deal with each of his counterparts across MLB.

Rays: Rockies (Jan. 28, 2016)
Acquired Corey Dickerson and Kevin Padlo for Germán Márquez and Jake McGee

The Rays have come out on the better end of many trades in recent years, but this isn't one of them. Dickerson played just two seasons for the club, while Márquez has gone on to become an integral piece of the Rockies' core.

Yankees: Mets (Dec. 14, 2014)
Acquired González Germen for cash

This was general manager Brian Cashman’s first deal with his team’s Subway Series foe in 10 years, having acquired pitcher Mike Stanton in December 2004. It didn’t amount to much, as Germen was designated for assignment less than a month later and traded to Texas.

Rangers: Nationals (Dec. 12, 2014)
Acquired Ross Detwiler for Christopher Bostick and Abel De Los Santos

It’s fair to say this one didn’t make nearly as much of a splash as the first trade between these two clubs after the Nats relocated to Washington. That one, in December 2005, sent Alfonso Soriano to D.C. just in time for him to post a rare 40-40 season.

Pirates: Rockies (Nov. 11, 2014)
Acquired Rob Scahill for Shane Carle

Pittsburgh in 2021 completed its first trade with St. Louis since 2000, acquiring John Nogowski for cash. With that, the Pirates' trade drought with the Rockies became their longest active drought.

Angels and Mariners (Dec. 19, 2012)
Los Angeles acquired Jason Vargas for Kendrys Morales

This intra-division challenge trade was the first between the American League West rivals since 1996 and just the fourth since Seattle debuted in 1977.

Red Sox: Astros (Aug. 3, 2012)
Sent Garrett Mock for future considerations

The Red Sox and Astros have been frequent postseason opponents in recent years, so this drought may not be ending anytime soon.

Marlins: Tigers (July 26, 2012)
Sent Brad Davis for future considerations

The Marlins and Tigers came together for two trades in a four-day span in July 2012. The first saw Detroit acquire Aníbal Sánchez and Omar Infante from the Marlins for Rob Brantly, Brian Flynn and Jacob Turner on July 23. This move went down three days later, and the two sides haven't made another trade with each other.

D-backs: Nationals (July 30, 2011)
Acquired Jason Marquis for Zach Walters

The 2011 D-backs surged in August and September to win the National League West, but it was not because they picked up Marquis. The veteran right-hander had a 9.53 ERA in three starts, went on the injured list and never pitched for Arizona again.

Padres: Tigers (Dec. 21, 2009)
Acquired Dusty Ryan for cash

What, no love for an old World Series opponent (1984)?

White Sox: Mets (May 30, 2009)
Acquired Ramón Castro and cash for Lance Broadway

A pitcher named Broadway going to New York? Unfortunately, there wasn’t much opportunity for the back-page editors to flex their muscles, as the 2005 first-round Draft pick lasted just eight games with the Mets, his final games in the Majors.

Mets: Twins (Feb. 2, 2008)
Acquired Johan Santana for Carlos Gomez, Deolis Guerra, Philip Humber and Kevin Mulvey

To seal this blockbuster trade, the Mets agreed to sign Santana to a six-year, $137.5 million contract. The left-hander gave the club three strong seasons and threw the first no-hitter in franchise history before injuries cut his career short. None of the players the Mets gave up panned out in Minnesota, although Gomez went on to become a two-time All-Star with the Brewers and Humber threw a perfect game for the White Sox.

Giants: Dodgers (Aug. 9, 2007)
Acquired player to be named later (Travis Denker) for Mark Sweeney

In 1956, when these two franchises were still in New York, the Dodgers traded Jackie Robinson to the Giants, only to have Robinson retire rather than report to his new club, and the deal was voided. The arch-rivals soon moved west, but in the decades since, they have come together for only three trades, in 1968, '85 and finally, 2007. This last one was quite minor, with Sweeney, a veteran pinch-hitter, getting 21 hits in a Dodgers uniform over the next two seasons.

Cubs: Cardinals (July 4, 2007)
Acquired John Nelson for future considerations

Believe it or not, the Cubs have made more trades with their bitter NL Central rival (74) than any other franchise, though of course much of that is due to their long shared history. Only three of those have occurred since 1981, and this most recent one barely registered, as Nelson, who got into eight games with the 2006 Cards, never played in Chicago. Brock-for-Broglio this was not.

Astros: Nationals (March 26, 2007)
Acquired Danny Ardoin for Wade Robinson

The only trade between these 2019 World Series opponents and Spring Training neighbors -- since the Washington franchise moved from Montreal -- involved players who never suited up for either big league club.

Twins: Reds (July 31, 2006)
Acquired Zach Ward for Kyle Lohse

Lohse had a 7.07 ERA when the Twins shipped him to the Reds at the 2006 Trade Deadline. He was traded again a year later, this time going from Cincinnati to Philadelphia. Ward never appeared in the Majors.

Reds and Cardinals (April 21, 2006)
St. Louis acquired Timo Pérez for cash

Cincinnati has made only four of its 98 all-time trades with St. Louis in the 26 years since the teams became sometimes-testy division opponents in the newly formed NL Central.

Brewers and Rockies (Dec. 13, 2004)
Colorado acquired Marcos Carvajal for cash

These teams also matched up for one of the first -- and most notable -- trades in Rockies history. The expansion franchise nabbed Dante Bichette from the Brewers in November 1992, before it ever played a game.

Indians and Royals (June 4, 2004)
Kansas City acquired Matt White for future considerations

By this point, White (a 1998 Cleveland Draft pick) had already been selected in the Rule 5 Draft twice, only to be returned to the Indians.

Dodgers and Tigers (April 1, 2004)
Los Angeles acquired Cody Ross for Steve Colyer

This was one of the first moves made by Paul DePodesta after the Dodgers hired him as GM in February 2004. Ross, 23 at the time, played only 22 games with the Dodgers, but he stuck in the Majors through ‘15 and was MVP of the 2010 NLCS for the Giants.

Braves and Phillies (Dec. 20, 2002)
Atlanta acquired Johnny Estrada for Kevin Millwood

It’s been quiet for these NL East rivals since Atlanta shipped away Millwood, supposedly in large part for budgetary reasons, after a season in which he went 18-8 with a 3.24 ERA.

Nationals/Expos and Orioles (Oct. 3, 2001)
Baltimore acquired Tim Raines for future considerations

The Hall of Famer’s second stint in Montreal ended when the 42-year-old was traded near the end of the season so he could play with his son, Tim Raines Jr., who had recently debuted for Baltimore. They joined the Griffeys as the only father-son teammates in MLB history.

However, these two franchises have not agreed to a trade since the Expos moved to the Mid-Atlantic and became the Nationals in 2005, creating some regional tension.