The Mets thought for weeks that locking up Kris Benson would be the most difficult part of their offseason pitching acquisitions, with Leiter a sure bet to follow.
But a stalemate in negotiations, exacerbated by a reported one-year, $7 million offer from the Florida Marlins, have prompted both sides to explore what Mets GM Omar Minaya called "other options."
While Leiter is looking for only one more year before he retires, the Mets will not match Florida's offer financially. At 39, Leiter is no longer a sure bet to bring games past the sixth inning, while the torn labrum in his pitching arm is a cause for concern, despite the fact he was 10-8 with a very respectable 3.21 ERA this season.
Whether Leiter wants to return to the Marlins, where he won a World Series in 1997, is another story altogether – a recognizable face in New York thanks to his numerous charity and political appearances, Leiter might opt for less money for the convenience of pitching across town with the New York Yankees.
None of that is the Mets' concern for the moment, as the club now must figure out who will comprise the one vacant hole in a pitching staff that is currently made up of Benson, Tom Glavine, Victor Zambrano and Steve Trachsel (the last of whom could be dealt before spring training).
Options from within include Jae Seo and Aaron Heilman, but neither pitcher has been able to enjoy consistent success on the major league level – in fact, the New York Daily News reported this week that Seo told the Korean media that he was entertaining the idea of leaving the Mets, a direct result of his frequent demotions to Triple-A Norfolk and past clashes with pitching coaches Vern Ruhle and Rick Peterson.
If the Mets decide to delve into the free agent market for starting pitching, they'll have no shortage of possibilities. A brief rundown:
Matt Clement, RHP: Rumor has it that the Mets' top choice to replace Leiter in the rotation would be Clement, who posted an unimpressive 9-13 record for the Chicago Cubs this season but fanned 190 batters in 181 innings.
A hard-throwing righthander, Clement has been a much better pitcher since moving to Chicago from the Florida Marlins, posting ERAs of 3.60, 4.11 and 3.68 in his three years with the Cubs. His money pitches are a low-90s sinking fastball and slider, both of which boast significant movement.
Jon Lieber, RHP: The Yankees' gamble on Lieber paid dividends in 2004, but it was mostly mixed results from this veteran.
A control artist to the fullest, Lieber went 14-8 in his first full season back from Tommy John surgery, but much of it was thanks to the Yankees' vaunted offense. Opponents hit .301 against Lieber for the season and he finished with a very median 4.33 ERA.
With the right offense behind him, the one-time 20-game winner (2001 with the Cubs) could very well repeat that feat, but it probably wouldn't be with the Mets.
Derek Lowe, RHP: The Mets showed some early interest in the Boston Red Sox postseason hero, who notched victories in each of Boston's three October clinching games.
A sinkerball pitcher, Lowe could be a nice fit in Shea Stadium, but some have expressed concern that a big contract would only diminish a work ethic that Red Sox insiders have already characterized as suspect.
Pedro Martinez, RHP: The Boston Herald reported on Wednesday that the Mets have officially entered the running for Martinez, making New York the third club to enter the ring.
Boston still remains Martinez's most likely destination, as the Sox have offered Martinez a two-year deal worth $25.5 million with an easily attainable third year, but it could be interesting to see how the Mets and Yankees battle under Martinez's famous mango tree.
Martinez is no longer the dominant, untouchable pitcher he was in his prime, but he still has the ability to become a very solid piece of whatever rotation he winds up in.
Eric Milton, LHP: Milton represents an intriguing left-handed option to replace Leiter, which could provide balance to a starting five that currently only has Glavine throwing from the left side.
Milton did a good job with the Philadelphia Phillies this year, going 14-6 with a 4.75 ERA, but many are still waiting for him to post a big breakout year. At the very least, the 29-year-old Milton handled his switch to the National League with aplomb and familiarized himself with the Mets' divisional rivals.
He was 0-1 with a 5.82 ERA in three starts against the Mets, all of them at Shea Stadium.
Carl Pavano, RHP: The Mets have some serious competition if they are intent on aggressively pursuing Pavano, which makes it more likely that they'll step aside and let the Red Sox and Yankees duke this one out.
Pavano, who was 18-8 for the Florida Marlins this year, has already familiarized himself with Curt Schilling's Massachusetts home and has set a date to meet with the Yankees in December, at which time the Mets are likely to drag him over to Queens for a visit.
Brad Radke, RHP: Radke is seriously considering staying with the Minnesota Twins, who have offered him $15 million over two years, but he has received interest from the Red Sox, Yankees and Phillies. That puts him on the Mets' radar as well, and New York could do far worse than this righthander with a smooth delivery and good control.
Barry Zito, LHP: It was difficult not to draw the connection between Zito's so-so season – just 11-11 with a 4.68 ERA, after four very impressive years with the Oakland Athletics – and the departure of pitching coach Rick Peterson to the Mets.
Zito relied heavily upon Peterson's presence and mental analysis of pitching, which is part of what has sold the Mets enough to unofficially name Peterson their "C.E.O. of pitching."
The southpaw is not a free agent, but the Mets have chips to deal – Mike Piazza, for one, has been named as a candidate to be shipped to the West Coast, albeit not yet to the A's.
Bryan Hoch is a frequent contributor to Scout.com.