The Twins already had pried a future All-Star closer (Joe Nathan) and a projected innings-eater (Boof Bonser) out of the Giants for catcher A.J. Pierzynski.

But what really elevated that November 2003 deal to legendary status was the last name to make the list: Francisco Liriano, then a Class A left-hander.

If Liriano wasn't a throw-in, he was darn close. A semi-throw-in, if you will, thanks to the scouting work of a man named Sean Johnson.

"I would say semi would probably be the right expression," says Twins general manager Terry Ryan, Sporting News 2006 executive of the year. "We had good reports on him. He'd just been hurt."

Whatever you call him, Liriano remains — despite offseason elbow surgery — the classic cautionary tale for any baseball deal maker. It's often that last piece you relinquish that comes back to bite you.

"You always try to squeeze one more player out of any deal you make, and the other teams try to squeeze one more out of you," Brewers GM Doug Melvin says. "You might take a player out of rookie ball or a Latin player."

Melvin got one such piece from the Giants — not to pick on their GM, Brian Sabean — in exchange for left-hander Wayne Franklin in 2004, and Carlos Villanueva could open next season in the Brewers' rotation.

Dontrelle Willis? The Marlins were more excited about a young catcher named Ryan Jorgensen when they dealt Matt Clement and Antonio Alfonseca to the Cubs in 2002.

All the D-Train has done since then is become the face of the franchise.

"I wouldn't call him a throw-in," says Cubs GM Jim Hendry, then an assistant to Andy MacPhail. "Dontrelle had played a year and a half, signed late, and at that time we had (Hee-Seop) Choi and (Bobby) Hill and Juan Cruz, and they were all better rated."

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On the flip side, Hendry was able to get left fielder Matt Murton just before the trading deadline from the Red Sox in July 2004.

That was the famous four-team deal that sent Nomar Garciaparra to the Cubs, Orlando Cabrera and Doug Mientkiewicz to the Red Sox and other pieces to the Expos and Twins. There had been steady talks between the Cubs and the Omar Minaya-led Expos regarding Cabrera, but Hendry wanted to hold on to infield prospect Brendan Harris.

That's when Red Sox GM Theo Epstein got creative.

"Theo, in the last 10 to 15 minutes, offered Murton to Omar, but Omar preferred Harris," Hendry recalls. "I said, 'Heck, I'll take Murton.' We liked him then. We really like him now. That's probably the best (throw-in) we've gotten."

Six months later, Epstein called Hendry and tried without success to get Murton back.

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"That one hurt a little," Hendry says. "Those kinds of trades do."

Dave Roberts, another key cog for the 2004 Red Sox, was a throw-in much earlier in his career. In June 1998, the Tigers sent the speedy outfielder — then at Class AA — to the Indians with Geronimo Berroa for Tim Worrell. Six years later, Roberts had the most famous stolen base in Red Sox history.

Speaking of curse busters, Curt Schilling was essentially a throw-in two different times early in his career.

In July 1988, he went from the Red Sox to the Orioles along with Brady Anderson (the key piece) for veteran pitcher Mike Boddicker. After going 1-6 in parts of three seasons with Baltimore, Schilling was shipped off again in 1991, this time to Houston as the third (and last) piece for first baseman Glenn Davis.

The first two players the Astros received were Steve Finley and Pete Harnisch.

"They picked the right guys," says Melvin, an Orioles assistant for both deals. "Schilling was probably the lesser of the players at that particular time again."

That's why GMs sweat the throw-ins as much as the main attractions.