The 28-year-old Suzuki, who had played all five-plus of his major league seasons with Oakland, is batting .218 with a home run and 18 RBIs. Nationals manager Davey Johnson said he expects Suzuki to report in time for NL East-leading Washington's Saturday's home game against Miami.
In a strange twist, the A's traded Gio Gonzalez to the Nationals in December and received both lefty starting pitcher Tommy Milone and catcher-of-the-future Derek Norris. Now, Suzuki will get to catch the All-Star Gonzalez again, across the country in the NL.
Still, Oakland general manager Billy Beane said when Norris was promoted this spring it didn't necessarily mean Suzuki would be on the trading block. Everybody expected him to be gone soon, however.
"It's a chance for us to move forward with Derek and a chance for Zuk to play every day somewhere else," A's assistant general manager David Forst said.
Washington wanted to improve its catching after the loss of Wilson Ramos with a torn anterior cruciate ligament. Jesus Flores has been the starter, though Johnson referred to Suzuki as "a No. 1 catcher."
When Nationals General Manager Mike Rizzo brought up Suzuki to Johnson, the manager enthusiastically endorsed the acquisition.
"I said, 'Man, that would definitely bolster our catching corps,'" said Johnson, who managed Suzuki in a 2006 U.S. Olympic qualifying tournament.
Oakland is picking up some of the salary owed Suzuki, who is signed for $5 million this year and $6.45 million next season. His contract includes an $8.5 million team option for 2014 with a $650,000 buyout.
"He's in the Gold Glove conversation each and every year," Rizzo said. "He's not a rental. He's going to be here for more than this season."
Flores had surgery on his right shoulder in September 2009 and missed the following season. He's batting .225 with three home runs and 18 RBIs and has has thrown out just five of the 48 runners attempting to steal. Suzuki has thrown out 38 percent of runners this season.
"Flo is still having some problems. He's not back to where he was," Johnson said.
Freitas was batting .271 for Class-A Potomac.