Sick, I would retire that guy immediatlely. You just started this guy and tackling is not what you want. Speed is the common attribute to all. How are you gonna knock someone out when you can't catch them...right? If you want a successful player then you should match your effective level at least til level 9. Go ahead and get you some speed, then if you want to be a "Steve Atwater" type of tackler then get your tackling. I'd concentrate on speed, agility. vision, jumping then get a lil stamina. If you want to train tackling then thats fine. I'd train it with strength. Its a nice combo. I've never used SP for tackling or strength for a defensive back. Like Parasite pretty much said, If you want a run stopper then build him however you want him, but the attrbutes I gave you are a MUST. Get those first then hit it up with the tackling skills