WASHINGTON -- A baseball source confirmed on Wednesday that the A's have examined Nationals first baseman Nick Johnson's medical records, but the clubs have not yet talked about a possible trade.

The news was first reported by FOXSports.com. The source also said that several other teams have Johnson's medical records. The Nationals would not confirm that such a transaction between them and the A's took place.

Johnson has been the Nationals' regular first baseman since they moved to Washington in 2005, but he could be expendable if the Nationals sign free-agent first baseman Mark Teixeira, who has been the team's top target this offseason.

In other news, a few weeks after electing free agency, right-hander Ryan Wagner signed a Minor League deal with Washington earlier this week.

Wagner, who was part of the eight-player trade that sent left-hander Bill Bray to the Reds in 2006, didn't play a Major League game for the Nationals this season in part because of right shoulder problems. However, he played for Triple-A Columbus and went 0-3 with a 5.68 ERA in 16 games.