Carlos Delgado, the injured first baseman of the Mets, took batting practice Thursday during a simulation of game conditions and said he was almost ready to return from the right hip flexor injury that has idled him since Sept. 5. But Luis Castillo, the second baseman, was a late scratch from the starting lineup against the Florida Marlins because his right knee, a chronic problem this season, was too sore for him to play. Before the Mets opened a four-game series, Delgado said: ?It was a pretty good test facing a real pitcher. It?s been a long 16 days. Nobody likes to be hurt. It?s not 100 percent. It?s significantly better. I?m able to do a lot more stuff.? Delgado batted against Jos? De La Torre, a minor league prospect. In Delgado?s last appearance, during an 11-7 victory at Cincinnati on Sept. 4, he had three hits to raise his batting average to .255, a season high. He has 22 home runs and 80 runs batted in.