* SoftBank contributes hefty 51 points to Nikkei * Next support line seen at 14,000 - fund manager * Nikon stumbles after criticized at China consumer show By Ayai Tomisawa TOKYO, March 17 (Reuters) - Japan's Nikkei share average hovered near a one-month low on Monday morning as escalating tensions in Ukraine dampened risk-appetite, though SoftBank Corp soared after its affiliate said it would go public in the United States. Trading was choppy as investors remained on edge after citizens of Crimea voted overwhelmingly to break with Ukraine to join Russia on Sunday. The Nikkei was flat at 14,332.33 in midmorning trade after tumbling 3.3 percent to 14,327.66 on Friday, the weakest closing point since Feb. 14. The benchmark dropped 6.2 percent last week, marking the biggest weekly drop since last June. Traders said the mood was cautious after over 90 percent of Crimean voters chose to break with Ukraine and join Russia on Sunday, an outcome that was denounced by Western powers and leaders in Kiev as a sham. President Barack Obama told Russian President Vladimir Putin in a phone call on Sunday that the United States rejected the results of a referendum in Ukraine's Crimea region and warned that Washington was ready to impose sanctions on Moscow over the crisis. The Nikkei's downside appears to be limited as some investors are keen to buy back stocks on dips at the current level, traders said, noting that Japanese companies' fundamentals are solid. "You can't justify Japanese companies' recovering earnings with the current Nikkei level," said a chief portfolio manager at a Japanese asset management firm. "Reasons for selling are all due to external factors. As soon as tensions over Ukraine ease further, people will likely buy back." SoftBank was the main focus in early trade, jumping as much as 6.6 percent to a seven-week high of 8,239 yen and was the most traded stock by turnover after its Chinese e-commerce affiliate Alibaba Group Holdings decided to hold its long-awaited share listing in the United States. Softbank contributed hefty 51.45 points to the index. Nikon Corp dropped 4.2 percent to 1,686 yen, the lowest since Feb. 6 after being criticised on a closely watched consumer show that said the camera maker had sold defective products in China and denied local consumers fair treatment in aftersales service. Exporters lost ground as the dollar held below 102 yen. Sony Corp dropped 1.9 percent, while Panasonic Corp shed 1.4 percent. A strong yen cuts Japanese companies' competitiveness abroad and erodes their offshore dollar profits when repatriated. The dollar was last traded at 101.53 yen. The broader Topix index shed 0.3 percent to 1,160.74. The JPX-Nikkei Index 400, a gauge comprising firms with high return on equity and strong corporate governance, dropped 0.5 percent to 10,488.09.