Tokyo's benchmark Nikkei index closed marginally lower on Monday, playing catch-up after a four-day weekend, with global risk aversion on intensifying US-China tensions. The Nikkei 225 index fell 0.16 percent, or 35.76 points, to 22,715.85 but the broader Topix index gained 0.24 percent, or 3.73 points, to 1,576.69. si/sah/gle