Thousands of commuters faced severe hardship on Monday, when the Delhi Metro schedule went haywire due to the collapse of the Northern Grid. Traction power supply to all Metro lines/depots was cut off from 2.35 am to 6.58 am. Metro trains were rolled out from respective depots for passenger services in a phased manner with 25 per cent services at around 7 am. Normal services could be resumed only around 9 am.