There were too many unwise trades, free-agent signings and draft selections in New York sports during the 2000s to list here, of course. But let's look back at 10 of the worst, shall we?
The lifelong Knicks fan from Coney Island came home in a 2004 deal with Phoenix for Howard Eisley, Charlie Ward, Antonio McDyess, Maciej Lampe, the draft rights to Milos Vujanic and two first-round picks.
Initially, the trade seemed to work; the Knicks rallied to make the playoffs, where they were swept by the Nets. In his first full season with the team, he averaged 21.7 points a game. But in the next three seasons, Marbury never averaged more than 16.4 points a game and the team failed to return to the playoffs.
Feuds with three different coaches over his role and playing time eventually led to his being told to stay away from the team. He and the Knicks - who are owned by Cablevision, which also owns Newsday - parted ways in February after agreeing to a buyout.
2. Carl Pavano, Yankees signing, Dec. 20, 2004
Handing Pavano nearly $40 million for four years seemed sane enough after he went 18-8 with the Marlins in '04. But no.
Pavano would go 9-8 as a Yankee, slowed by injuries to his shoulder, tush and ribs, the last from a car accident he initially failed to disclose to the team.
3. Victor Zambrano, Mets trade, July 31, 2004
Zambrano would finish 10-14 in his Mets career. Kazmir went 55-44 with Tampa Bay, including a 239-strikeout season in 2007, before being traded to the Angels late in '09.
4. Eddy Curry, Knicks trade, Oct. 3, 2005
Landing a huge, young center with skills made sense on paper, but Curry has not proven worth the price, which included a pair of first-round draft picks to the Bulls.
Curry had a strong 2006-07, averaging 19.5 points - including a 43-point game - and 7.1 rebounds. But the pairing with Zach Randolph in '07-08 was a dud, and he played only three games last season.
The problem wasn't the selection of DiPietro as much as what led to it: "Mad Mike'' Milbury trading Roberto Luongo and Olli Jokinen for Mark Parrish and Oleg Kvasha, then taking DiPietro ahead of Dany Heatley and Marian Gaborik.
Six years later, the Isles inked DiPietro to a 15-year contract. He played five games last season and none so far in 2009-10.
6. Mo Vaughn, Mets trade, Dec. 27, 2001
Alas, he was out of shape in 2002, finishing with 26 home runs and 72 RBIs. He played in 29 games in '03 before a knee injury ended his career. Appier and the '02 Angels won a World Series.
7. Ron Dayne, Giants draft pick, April 15, 2000
The Heisman winner and leading rusher in major college history was the 11th pick in the draft - taken before future star back Shaun Alexander - and was to join Tiki Barber as "Thunder and Lightning.''
Mostly, Dayne was no more than a distant rumble. His rushing yardage declined steadily, from 770 as a rookie to 179 in '04. Then he was gone.
8. Kevin Brown, Yankees trade, Dec. 11, 2003
Kei Igawa got consideration here, but Brown was a more compelling figure as his otherwise successful career wound down in injury-riddled angst.
In '04, he went 10-6, broke his non-pitching hand when he punched a wall in frustration, then was torched for five runs by the Red Sox early in Game 7 of the ALCS. He went 4-7 in '05 and was done.
The Islanders sent the No. 2 overall pick in the draft - which became Jason Spezza - and two veterans (including Zdeno Chara) to the Senators for Yashin, whom they then signed to a 10-year, $87.5-million deal.
After a 32-goal, 43-assist season in 2001-02, his production fell off, and he never justified the price the team paid for him. He totaled five goals in 22 playoff games as an Islander.
Favre was no bust with the Jets, leading them to an 8-3 start and selling many replica No. 4 jerseys. But in the end, he was guilty of being a tease.
The team and quarterback collapsed down the stretch to finish 9-7, and the NFL's most melodramatic diva soon was out the door en route to another brief retirement before landing where he wanted to be all along: Minnesota.