What does the Charger defense need to change to become stronger against the Colts?

Do they need to run a 4-3? And don’t bother answering if your gonna say the Colts are gonna smash the Chargers, That’s all we heard last season, and the Chargers beat the Colts in their own Stadium, but what is the Charger defense missing besides Merriman?

What does the Charger defense need to change to become stronger against the Colts?