TOKYO, Feb 27 (Reuters) - Japan's Nikkei average fell for a second day on Thursday, moving further away from a four-week closing hit earlier this week as heightened tensions in Ukraine soured sentiment, dragging down index heavyweights like SoftBank. The Nikkei ended 0.3 percent lower at 14,923.11, moving away from 15,051.60 hit on Tuesday, which was the highest closing level since Jan. 29. Index heavyweights lost ground, with SoftBank Corp falling 1 percent and Fast Retailing Co dropping 1.7 percent. The broader Topix index slipped 0.7 percent to 1,217.35. The JPX-Nikkei Index 400, an index launched this year comprising firms with high return on equity and strong corporate governance, dropped 0.7 percent to 11,009.41.