How to avoid worldly distractions in concentrating on Krishna?

From: Birendra

A few years ago I was able to concentrate on Lord Krishna. But nowadays I find it hard to offer prayer even for two minutes. My mind wanders away from him and what enters my mind is job pressure, work load, office politics, family matters, all that nonsense. How to control the mind so that it is concentrated on the chanting of Lord Krishna’s name, even for two minutes only?