WASHINGTON -- Left-hander John Lannan asked the Washington Nationals for a trade after they demoted him to Triple-A Syracuse, and he declared in an email sent to reporters on Wednesday: "I believe that I belong in a big-league rotation."
Under the subject line, "Thoughts on announcement of being optioned," Lannan wrote that he told general manager Mike Rizzo "a trade would be the best solution for everyone in both the short and long term."
"I am certainly disappointed in the Nationals' decision. I met with Mike Rizzo for the second time since I received the news to tell him exactly how I feel, and my agent has also spoken to Mike," Lannan wrote. "I know what my rights and the team's rights are. ..."
Before Thursday's season opener against the Chicago Cubs at Wrigley Field, Rizzo declined to gauge the chances that Lannan could be traded. He said the Nationals have fielded some calls from other clubs but are not "shopping'' Lannan and characterized interest in the left-hander as "mild.''
"We're going to listen for offers and seek opportunities,'' Rizzo said. "If we see an opportunity and the offer is there and we can get some value (in return), we certainly believe he's a major league pitcher and he should be in the major leagues in a lot of rotations.''
The Nationals surprisingly optioned Lannan to the minors on Tuesday, deciding to give the No. 5 spot in their season-opening rotation to another lefty, Ross Detwiler. While Detwiler spent much of 2011 at Syracuse, Lannan was making 33 starts for the Nationals, going 10-13 with a 3.70 ERA over 184 2/3 innings. He led the club in starts, wins and innings.
The 27-year-old Lannan is slated to earn $5 million in 2012. He was drafted by the Nationals in the 11th round of the 2005 amateur draft, moved quickly through their system, and was Washington's Opening Day starter in 2009 and 2010.
"I appreciate all the opportunities the Nationals organization has given me throughout the years. I've done a lot for this organization through some tough times. I anticipated ... being part of the team's next exciting chapter," Lannan wrote Wednesday. "If the Nationals feel they don't need me or want me with the current make-up of the team, I can respect their decision. However, I'm very confident that I am capable of making a meaningful contribution to a major-league team."
Since making his big league debut in 2007, Lannan is 38-52 with a 4.00 ERA in 128 appearances, all as a starter.
"I am a proven major-league starting pitcher, with a track record of success," he wrote.
Rizzo was not surprised by Lannan's reaction to being sent to Triple-A.
"If he was happy and he took this laying down, it wouldn't be John Lannan,'' Rizzo said. "And you'd have to worry about that type of person. This guy is an ultra-competitive, professional pitcher who was upset and mad when we sent him down. He and I had two conversations after we made the decision, and they were uncomfortable. But at the end of the day he was professional and respectful, and he knows he has to do his thing.''
Nationals manager Davey Johnson said Tuesday he informed Lannan of the move to Syracuse in the third inning of that day's 8-7 loss to the Boston Red Sox.
"Johnny's a good friend," Detwiler said Tuesday after Washington's exhibition finale. "You never want to see a good friend leave the clubhouse. ... It's kind of bittersweet seeing Lannan go. But I also get a chance to start now."
ESPN.com senior baseball writer Jerry Crasnick and The Associated Press contributed to this report.