Yokozuna Kakuryu and sekiwake Tochinoshin each won on Day 5 of the Summer Grand Sumo Tournament on Thursday to retain their share of the lead.

Kakuryu overcame a spirited but short-lived effort from Bulgarian komusubi Aoiyama in the final bout at Ryogoku Kokugikan, whileTochinoshin bested top-ranked maegashira Hokutofuji in an earlier bout.

The only other top-division wrestler to remain undefeated after five days of action is No. 8 Asanoyama.