Werth, who shed his trademark scraggly beard for a more trimmed look, donned the No. 28 jersey he will wear next season.
Werth, 31, acknowledged that the length of the contract and conversations with members of the front office were the reasons he decided to join the Nationals.
"When you get into free agency, you have a chance to do something special for yourself and for your family," Werth said. "Obviously, the years were important to me. I have a chance to come to a city where I'm guaranteed to be here for a long time. The no-trade was a big deal for me. I set myself and my family up for years to come. It's more of a solid base.
"[The Nationals] have some talent. It's very young and unpolished and that's one thing I look forward to helping along the way. I've always been a big fan of an underdog, and the situation here in Washington -- we're going to put something together that the city and fans will come to love and come to see us on a nightly basis."
After losing free agent Adam Dunn to the Chicago White Sox, the Nationals were looking for a player in the middle of the order. General manager Mike Rizzo felt that Werth was one of the top targets because he could hit for power, play solid defense and has above-average speed.
The talks between Werth and the Nationals became serious after the General Managers Meetings. Rizzo, managing principal owner Ted Lerner and principal owner Mark Lerner met with Werth in California. They explained their game plan to the right-handed-hitting slugger, who was impressed by what he heard.
"He is the total package," Mark Lerner said. "Every time he shows up here, he seems to hit a home run against us. Even if you are not on his side, you can't help but be impressed with what he leaves on the field. He will be a great addition, not only on the field, but in the clubhouse -- help turn the culture around. We want to continue to press forward to get the right-winning culture."
Before getting a deal done, Rizzo acknowledged that the biggest hurdle was adding a no-trade clause to Werth's contract. Rizzo said that he was reluctant to put in such a provision.
"It was very difficult -- last sticking points that we had," Rizzo said. "I would [not] rather have a no-trade clause. It's another impediment to roster construction. ... The no-trade clause gives the player more control. ... We certainly are not going to make it a habit. It's something for elite free agents like [Werth]."
With Werth being the highest-paid member of the Nationals, it means that he has a big role in carrying the team offensively and defensively. Werth welcomes the challenge.
"Anytime you play for a team, there is going to be pressure," Werth said. "I'm coming to this team and this city to be involved in something much greater that you have seen before. The owners are on board, Mike is on board, [manager] Jim [Riggleman] is on board. We are going in the same direction. I don't see any undue pressure. I will go out and play my game. I will come to the field ready to play. I look forward to going to war with the guys, who are in the clubhouse and get the job done."
Werth will play right field against right-handed starting pitchers and will likely protect Ryan Zimmerman in the lineup. Riggleman also indicated that Werth most likely will play center field when an opposing left-hander is on the mound.
Werth had arguably his best year in the big leagues this past season, hitting .296 with 27 home runs, 85 RBIs, 106 runs scored and 13 stolen bases for the Phillies. By many accounts, Werth carried the Phillies in 2010, when Ryan Howard, Jimmy Rollins and Chase Utley all missed time with injuries.
"You have a guy that could hit 30 home runs ... play Gold Glove defense, steal 20 bases, lead in the clubhouse and be a middle-of-the-lineup hitter," Rizzo said. "The bigger the game, the better he has played in his career. He is playoff-battle-tested. He brings an edge to the ballclub. I've seen it too many times with the Phillies. He is the type of guy that we want. His skill set is what Jim and I are looking for."
By the time the seven-year deal expires, Werth plans to play past the age of 40. He wants to have a long career like his grandfather, Ducky Schofield, and uncle, Dick Schofield.
"My grandfather played 19 years in the big leagues, my uncle played a long time. I feel like I'm really young in the game," Werth said. "I feel I have a lot of years left."
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the time. He also could be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.