The Pirates are engaged in intense discussions to trade Mark Redman to Florida and could do so this week, pending the outcome of the Marlins' efforts with the Baltimore Orioles to pull off a much larger deal. This is how things are shaping up: The first step would be a seven-player trade between Florida and Baltimore. The Marlins would send starter A.J. Burnett, third baseman Mike Lowell and center fielder Eric Reed to the Orioles for outfielder Larry Bigbie and pitchers Jorge Julio, Steve Kline and Hayden Penn. After that, the Pirates would send Redman to Florida for Bigbie. And if Bigbie is not available, negotiations could turn in a different direction. Sources in Pittsburgh, Miami and Baltimore yesterday stressed nothing is done on any front.