We rarely see sure things on baseball's trade market, those players who are certain to make a team better and improve its chances of not only winning a playoff spot, but also winning the World Series.

David Cone, the original hired gun, was a sure thing when the Blue Jays stunned the baseball world by acquiring the right-hander from the Mets in August 1992. Randy Johnson was a sure thing when he went from the Seattle Mariners to the Houston Astros in 1998. You knew Manny Ramirez was going to make his next team better after he forced his way out of Boston, and sure enough, Ramirez went to the Dodgers and single-handedly shifted the balance of power in the National League West by hitting .396 and driving in 53 runs in 53 games.

Cliff Lee is a sure thing, maybe the best sure thing since Johnson in 1998. There are no questions about him, no doubts. He is healthy and he is pitching at an extraordinarily high level -- he has 78 strikeouts and five walks so far this season. Everybody knows how he will handle a midseason trade, because he went from the Indians to the Phillies last year and thrived. Everybody knows how he will handle a shift in leagues. Everybody knows how he can pitch in October, given his incredible performance against the Yankees in the World Series.

Jack Zduriencik, the Seattle general manager, mentioned over the phone Tuesday afternoon that as good as he thought Lee was before acquiring him in a trade with the Phillies this past winter, he has become even more impressed since being around him on a daily basis. "You see the impact he has on teammates on the days he pitches," Zduriencik said. "You see the work he puts in. You see him in the clubhouse, the work he puts in. There is no wasted motion."

Zduriencik is playing the poker game, as he should. "We're trying to win baseball games," he said. "Teams are calling, and I can't control that."

Yes, in theory, the Mariners could keep Lee through the rest of this year. But that's not going to happen, because sometime in the next 31 days, some team is going to step up and offer a package of players that will include at least one position prospect good enough to anchor a deal for a pitcher who could transform a contender into a world championship team.

"He's the type of player who, if you get him, could be the difference between winning a championship or not," said one talent evaluator, who has been engaged in the early Lee trade talks. "He's that good. And I think the teams involved will ask themselves, 'What will it mean to our franchise if we were to win a World Series?' For a couple of teams, he could put them over the top."

It might be a shot worth taking. And for all the teams involved, right now is the time to dream of what Lee could mean to them.

The Mets: No team other than the Dodgers had a worse offseason of publicity than the team from Queens, with the nasty squabble between the club and Carlos Beltran, and the Mets' failure to land a starting pitcher for their rotation. But then Mike Pelfrey climbed into the elite tier, Ike Davis arrived, David Wright found his power stroke and Jose Reyes found his timing. At the start of Wednesday, the Mets were 1½ games behind the Braves and a game ahead of the Phillies. And if they were to get Lee, they would have as good a chance to win the NL East as anybody -- and seemingly would have an emotional leg up on the Phillies, who would have to compete against a pitcher who they know first-hand is capable of greatness.

The Mets could envision an October rotation that is good enough to win: Lee, Pelfrey and Johan Santana, who might be better suited now as a No. 3, in the postseason, given his diminished velocity.

The cost for the Mets: I asked about a half-dozen talent evaluators how they envision the Mets structuring a trade for Lee that wouldn't include Davis, and there was near unanimity on a couple of points. First, middle infielder Ruben Tejada -- a 20-year-old the Mets love -- is not good enough to anchor a deal for Lee. One official said his team is "lukewarm on Tejada and would not see him as a cornerstone piece in a Lee/Roy Oswalt/Dan Haren type deal. We like the Flores kid but I am a little skeptical that he'd be the primary piece at this point [early July] for Lee."

Wilmer Flores, an 18-year-old third-base prospect who is hitting .291 in Class A this year, has enough upside as offensive player to anchor a deal, the evaluators agreed, so long as the Mets also worked in a Tejada or Jenrry Mejia. Said one evaluator: "I think Seattle would eventually accept a deal with Flores, rather than hold Lee and take draft picks, but it would be closer to the deadline and after they've exhausted their primary targets with other clubs."

Said another evaluator: "Tejada is a nice player but not a very high ceiling. He is a second or third player in a deal."

From a third evaluator: "Tejada is a solid player who won't have a lot of impact."

The Twins: If Lee headed the Twins' rotation, said one GM last week, "that would be a very different-looking team going into October. That would be a team that could win it all." Minnesota battled its way into the playoffs last year and then had no suitable rotation weapons to beat the Yankees, nobody really capable of missing bats. But Francisco Liriano is missing bats this year, and a rotation with Lee in front of Liriano, Kevin Slowey and Carl Pavano could beat any team.

The cost: The Mariners need catching; the Twins have Wilson Ramos, a prospect widely regarded as good enough to anchor a deal for Lee. "I'd think that Ramos would be much better value in return as the primary piece for Lee than Tejada," one evaluator said.

Ramos is hitting just .218 in Triple-A right now, but of the eight evaluators I spoke with about him this week, seven offered resounding endorsements. "I think he's going to be a strong offensive catcher," one said. "He's got work to do on his defense, but he is going to hit." Which is what his history in the minors suggests, although he's never going to be confused with Adam Dunn as a walk machine.

"The Twins could build a deal around Ramos," an American League GM said.

They also could just hang on to Ramos; internally, the Twins have kicked around the potential value of keeping Ramos as part of a three-headed C/1B/DH monster in the years to come, with Joe Mauer/Ramos/Justin Morneau, a rotation that would allow proper rest for both Mauer and Morneau.

But it's a sure thing that Lee makes their chances of winning this World Series better.

The Dodgers: Folks within the organization would love to have him, and if you stuck Lee at the front end of the L.A. rotation, the Dodgers would immediately become favorites to win the NL West. In October, a rotation of Lee, Clayton Kershaw and two from the group of Chad Billingsley/Hiroki Kuroda/Vicente Padilla/John Ely could match up with any team. But there is zero expectation in many corners of the organization that the team will be given the internal go-ahead to pick up an expensive piece like Lee.

The Yankees: You wouldn't blame Joe Girardi for how great it would be to run out an October rotation of CC Sabathia, Cliff Lee, Phil Hughes and Andy Pettitte. But what the Yankees likely will do is hang on to prospects like Jesus Montero and pursue Lee -- and then run out an October rotation next year of Sabathia, Lee, Hughes and Pettitte (with A.J. Burnett somehow in the mix).

The Phillies: They believe the priority should be in adding a middle-of-the-rotation starter, somebody better than Jeremy Guthrie -- and in theory, they could pursue Lee. But rival evaluators believe it would be difficult for the Phillies to land Lee unless they gave up far more than what they got in return for Lee in December; the evaluators think they would have to give up young slugger Domonic Brown, which should be a non-starter.

It would be extremely difficult for the Phillies to think about a Lee deal, because let's face it, they would have to eat a lot of internal pride and essentially acknowledge a major mistake. The only thing worse, perhaps, would be seeing Lee stepping out of the other dugout in a Mets uniform.

The Rangers: Lee would fit the Texas needs perfectly and give the team a centerpiece for a rotation that doesn't have much in the way of big-game experience. And the Rangers are absolutely loaded with prospects and are probably armed better than any other potential Lee suitor to structure a deal for the left-hander.

But it's not clear how much financial flexibility the Rangers would have to pursue Lee, given the fact that the team is operating with help from Major League Baseball and its ownership is in a state of flux. It is possible for the Rangers to structure a trade that would enable them to swap something close to dollar for dollar; they could trade Rich Harden's contract for Lee's contract, with the Rangers giving Seattle a better package of prospects to convince it to take Harden's deal. The whole situation is complicated and might be difficult to pull off, and rival GMs believe the Rangers might be better off following a more disciplined course and keeping their prospects.

No matter what happens, the Mariners are going to get good players. It's just a question of who will step up and make the deal for Cliff Lee, a sure thing.

Buster Olney is a senior writer for ESPN The Magazine and an analyst for "Baseball Tonight." Read his daily ESPN.com blog here.

"Baseball Tonight" analysts, ESPN.com writers and SweetSpot Network bloggers chatted and gave their in-game opinions throughout the day's games -- all in Baseball Tonight Live.

Who went deep? Keep track of all the home runs hit each day on "Baseball Tonight" and the Baseball Tonight Clubhouse page. For more, check out the Home Run Tracker page.