The Washington Nationals agreed to trade right-hander Zach Day yesterday, but the deal was scuttled when an MRI exam revealed that the struggling pitcher has a hairline fracture of the right wrist, General Manager Jim Bowden said.

Bowden wouldn't reveal the other player or team involved in the deal.

"We finally got a deal that would help us win, and this happens," Bowden said prior to last night's game against the Atlanta Braves. "It's a tough day for us, but we'll overcome it."

Two baseball sources said the Nationals were in serious negotiations with the Florida Marlins about a deal that would have involved Day for outfielder Juan Encarnacion. Another source said the Nationals were also in negotiations with a team other than the Marlins.

Instead of making a trade, the Nationals placed Day on the 15-day disabled list.

In the last week, Day was struck in the right wrist by a line drive off the bat of Cincinnati's Ken Griffey Jr., gave up five runs in two innings two days later, was sent to the minors and underwent the MRI exam after pain persisted.

"It's been pretty bizarre," Day said by telephone. "The hits just keep on coming."

Day has said in the past month that he might benefit from getting a shot with another organization. Encarnacion is exactly the kind of powerful right-handed hitter Bowden has been seeking to provide some pop to the lower part of the Nationals' order.

X-rays of Day's wrist taken last week did not reveal any break. He pitched Wednesday, allowing those five runs to the Reds. But after he was demoted Thursday, he said he didn't feel that the injury was healing properly and told club officials. Still, he joined Class AAA New Orleans Monday in Nashville, where the minor league club is playing a series.

"I was there for about five hours," Day said. He then flew back to Cincinnati for an exam with Timothy Kremchek, the Reds' team physician who serves as a consultant for the Nationals. Kremchek took more X-rays yesterday morning -- they again came up negative -- but the MRI exam revealed the fracture. He is likely out for four to six weeks, the 11th National presently on the disabled list.

"As it turns out, I guess I threw 40 pitches with a fractured wrist," Day said.

Encarnacion, who played for Bowden in Cincinnati, is hitting .265 and slugging .459 with 33 RBI for the Marlins. The source said the Marlins would have had to pick up much of Encarnacion's $4.4 million salary.

Day, who was 1-2 with a 6.75 ERA in 12 appearances for the Nationals, said he wouldn't mind a trade, in part because he feels Nationals Manager Frank Robinson doesn't have confidence in him. Robinson disagrees with Day's assessment.

Bowden said yesterday, however, that he believes Day could still return to the Nationals and be effective.

"He can come back and win 15 games the next couple years," Bowden said. "I have all the confidence in the world he can. I believe in Zach Day. . . . He's a solid guy who got off to a slow start. Now, he had a bad break, and so did we."

Zach Day reportedly was headed to the Marlins. Instead, he was put on the 15-day disabled list.