Complex sentence: Still, the Atlanta Hawks felt Rider was the missing piece in their puzzle after the 1998-99 season, and so they sent Steve Smith to the Blazers for Rider and Jim Jackson, another talent who had not quite reached his potential.
Split into simpler sentences: Still, the Atlanta Hawks felt Rider was the missing piece in their puzzle after the 1998-99 season. So they sent Steve Smith to the Blazers for Rider and Jim Jackson, another talent who had not quite reached his potential.