PHILADELPHIA -- Welcome to the Phillies, Cinco Ocho.
The contract is the largest ever for a reliever, and it actually totals $50,000,058. The deal includes a vesting option for 2016 that could become guaranteed based on games finished and would make it worth $63 million over five seasons.
The option vests if Papelbon finishes 15 games in 2015 or finishes a total of 100 games in 2014-15, a baseball official familiar with the contract told ESPN.com's Jayson Stark.
So what about that extra $58?
"You'll have to ask Cinco Ocho that question," Papelbon joked. "I can give you his phone number if you need it."
Papelbon will wear No. 58, which belonged to lefty Antonio Bastardo last year. His nickname, of course, mimics Chad Ochocinco. The six-time Pro Bowl wide receiver legally changed his name from Chad Johnson to match his uniform No. 85.
Papelbon replaces Ryan Madson, also a free agent. The Phillies were negotiating with Madson's agent, Scott Boras, last week before going after Papelbon.
"He is among the elite closers in the game and someone who clearly has a passion to win," general manager Ruben Amaro Jr. said.
Papelbon, a four-time All-Star, turns 31 on Nov. 23. He had 219 saves over seven seasons with the Red Sox, including 31 this year, when he made $12 million. The right-hander helped Boston to the 2007 World Series title.
The Phillies have long been opposed to giving pitchers contracts beyond three years. They made an exception last year when they signed left-hander Cliff Lee to a $120 million, five-year deal.
"Four years is a little uncomfortable, but on a player like this and a person who has had this pedigree and this background and success, sometimes you go the extra mile to do that," Amaro said. "We felt he was the right guy to take a risk on."
Papelbon said talks with the Red Sox never really evolved.
"The Phillies showed they were interested in me and I wanted to make this decision quick and get it over with," he said. "I didn't want to sit there and debate on whether I go back to Boston.
"My agents called me every day with what could happen. One day I finally called them and said, 'Listen, I want to go play for the Phillies. Let's make it happen.' They called me two days later and made it happen."
The Phillies have won five straight NL East titles, but are coming off a disappointing end to a season in which they set a franchise record with 102 wins. Philadelphia was eliminated in the NL Division Series by eventual World Series champion St. Louis.
Since winning the 2008 World Series, the Phillies have regressed each season. They lost in the World Series to the New York Yankees in 2009, were eliminated in the NLCS in 2010 and got knocked out in the first round this year.
"The biggest thing in me coming here was playing against the Phillies the last four years, I really admired the way they play, I really admired the way they grind it out and I just feel like the guys in this clubhouse, the way they play the game of baseball is the way I play the game of baseball," Papelbon said. "I'm excited to meet the guys, I'm excited to play with them and I'm excited to compete with them."
Amaro said the Phillies still have payroll flexibility to re-sign shortstop Jimmy Rollins. The 2007 NL MVP is a free agent and said he wants to return to Philadelphia.
A starter in the minor leagues, Papelbon has thrived in the bullpen in the majors. He has converted 88.3 percent of his save opportunities to go with a 23-19 record and a 2.33 ERA in 396 career appearances. He had a career-high 41 saves in 2008.
Papelbon is the first major free-agent signing this year, and he's the first player to leave the Red Sox in a turbulent offseason that began with the departure of manager Terry Francona and was followed by general manager Theo Epstein going to the Chicago Cubs. David Ortiz, Jason Varitek, J.D. Drew, Tim Wakefield and Erik Bedard also are free agents.
The turmoil in Boston didn't factor into Papelbon's decision to leave. He blew a save on the final day of the regular season, completing Boston's monumental collapse that led to all those changes.
"I definitely feel the situation and the way it ended last year with Boston will make me a better pitcher," Papelbon said. "I'm not the type of player who is going to hide or shy away from being accountable as a pitcher. I've always pitched that way and gone about my business that way. I feel like in this role and as a closer you are not going to be perfect every day, but I sure am going to strive to be perfect every day."
If not, he can blame Cinco Ocho.
Information from ESPN.com's Jayson Stark and The Associated Press was used in this report.