Sosa's agent, Adam Katz, said late Wednesday night that Sosa more than likely will not play during the 2006 season, but the outfielder will not be put on the voluntary retirement list.
"It's very unlikely [that Sosa] will be in uniform. We are all trying to process this right now. It's big news," Katz told MLB.com late Wednesday night.
According to a source, Sosa wanted at least $1 million to sign with the Nationals, but Bowden was not willing to increase the offer. The Nationals had originally offered Sosa a Minor League deal with an invitation to Spring Training.
"We respect Sammy and what he has accomplished in the game," Bowden said. "We wish him well and hope that he is able to come back and perform like he did a couple of years ago. As long as he is not in our division, we'll be rooting for him to win Comeback Player of the Year."
A source familiar with the negotiations said that if Sosa was offered a deal similar to Frank Thomas, who received a $500,000 guaranteed contract with incentives from the Athletics, he would have taken the deal. But the think tank in the Nationals' front office was very concerned about Sosa's eroding skills.
Sosa is coming off the worst season of his career, hitting .221 with 14 home runs and 45 RBIs, and he had two stints on the disabled list with Baltimore. Sosa's last good season was in 2003, when he hit .279 with 40 home runs and 103 RBIs for the Cubs.
Katz said that Sosa did not reject the Nationals' offer because of money. Katz indicated that Sosa has high standards and he didn't want to risk having another disappointing season.
"It's not about the money or hitting his 600th home run. He is coming off a bad season, and he didn't want to disappoint the Nationals or the fans," Katz said.
If he doesn't return to the diamond, Sosa will leave the game with 588 home runs -- fifth most in Major League history -- 1,575 RBIs and a .274 career batting average. Sosa's best years were with the Cubs. Sosa had three seasons of 60 or more home runs, and he won the Most Valuable Player Award in 1998.
"It's a tough way to call it a career, if that's what he's doing," one source said.
Katz declined to comment on Sosa's future off the field.
The Nationals had looked at Sosa as Spring Training insurance in case Jose Guillen's injured left shoulder has not fully recovered or if Alfonso Soriano continues to refuse to play the outfield. Soriano may also play in the World Baseball Classic, which would keep him away from camp during the tournament.
With Sosa out of the picture, Marlon Byrd, Ryan Church and Brandon Watson will compete for the center field job. Had Sosa agreed to the deal, the Nationals would have had Soriano playing center field, with Sosa and Guillen at the corners.
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.