Rising sumo star Onosato offered an apology Wednesday for drinking alcohol with an underage fellow Nishonoseki-stable wrestler, two days after he was reprimanded over the September incident."I'm really sorry to have caused so much trouble," Onosato told reporters. On Monday, the Japan Sumo Association handed the 23-year-old and his stablemaster, former yokozuna Kisenosato, stern warnings over the incident that took place within the stable in Ibaraki Prefecture.Regarded as one of the sport's top prospects, Onosato posted back-to-back 11-4 records and vied for the championship in January and …READ FULL ARTICLE