General manager Omar Minaya has the closer he desperately needed. The rest of his team is still under construction -- just like the Mets' new ballpark.
Rodriguez and the Mets completed their $37 million, three-year contract when the record-setting reliever passed a physical Wednesday, filling a huge hole at the back of New York's deficient bullpen.
"It definitely gives us a good momentum," Minaya said. "It gives us a foundation, at least at the back end, and then the other guys that we have are fitting into a better role, roles that they are accustomed to."
Relief pitchers Aaron Heilman and Joe Smith were among the seven players dealt by New York for center fielder Jeremy Reed, right-handed reliever Sean Green and Putz, an All-Star closer in 2007 who becomes Rodriguez's setup man.
"All I kept on hearing in the streets of New York when you go get bagels in the morning was, 'Omar, please address the bullpen,'" Minaya said. "Well, to all you Mets fans, we've addressed the bullpen."
Before the trade was announced, Putz's agent, Craig Landis, said the right-hander wanted to remain a closer. But Minaya said he spoke with Putz, who was excited about his new team and role.
"To get one closer like Frankie would have been a good winter. I think to get two guys like this is a great winter," Minaya said.
Rodriguez's deal could be worth $53.5 million over four years, including an option and $2.5 million in performance bonuses. The 2012 option would become guaranteed if K-Rod stays healthy and finishes a certain amount of games.
All-Star closer Billy Wagner is expected to miss all of next season following elbow ligament replacement surgery, so the Mets had to find a replacement.
Moving aggressively at baseball's winter meetings, they landed the top reliever available on the free-agent market. Rodriguez saved 62 games for the Los Angeles Angels this year, five more than the previous major league mark set by Bobby Thigpen of the Chicago White Sox in 1990.
"I think the numbers speak for themselves but I think he adds confidence and a little swagger to the team," Mets third baseman David Wright said in an e-mail to The Associated Press. "He's a guy that has pitched in big playoff situations and has been to where we are trying to go. He has two or three pitches that he can throw in any count for strikes, and gets a ton of strikeouts."
"I just thought that when you look at the volume, there's Mariano and then there's Frankie -- statistically," the GM said.
Rodriguez's agent, Paul Kinzer, had hoped to get a five-year contract, possibly equaling the $15 million average salary Rivera is earning from the Yankees. The Mets were a natural fit because they were one of the few big-market teams looking for an elite closer this offseason. They also considered pursuing Brian Fuentes and Trevor Hoffman.
"I think it's a good deal for both sides," Minaya said. "It wasn't like he was the only one out there. That works on my side."
Because Johan Santana wears No. 57, Rodriguez will switch to No. 75.
"I'm thrilled to join the Mets," Rodriguez said in a statement. "Mets fans are very passionate and playing in a new ballpark is going to be great. I'm going to do everything I can to help bring a championship to Citi Field."
The ineffective bullpen was a big reason New York missed the playoffs again this year with its second consecutive September collapse. The Mets had 29 blown saves in 72 chances.
Minaya thinks K-Rod is equipped to thrive under pressure in New York -- though he could fit in with the Mets in another way, too: Some take exception to Rodriguez's antics on the mound, and the Mets have drawn the ire of opposing teams for their boisterous celebrations.
A three-time All-Star, Rodriguez turns 27 next month and his youth was one reason the Mets preferred him. While some teams were worried about his violent pitching motion and drop in velocity last season, he developed an outstanding changeup to go along with his other pitches.
"You like a nice, smooth-delivery guy. Much easier," Minaya said. "But it's that funkiness that helps him."
The additions of Rodriguez and Putz give New York a boost as it prepares for its first season at Citi Field, an $800 million ballpark in the final stages of construction adjacent to Shea Stadium.
The Mets still have an opening in their rotation. After signing K-Rod, Minaya said he doesn't expect to have the financial resources to get involved in serious negotiations with free-agent starters A.J. Burnett and Derek Lowe.
As of now, it appears the Mets will go to spring training with young pitcher Jon Niese and perhaps Bobby Parnell competing for the final spot in the rotation.