Yamamoto will still be searching for his first UFC victory. To date, he has lost three times, including a submission loss to Vaughan Lee at UFC 144 in Feb. 2012, his last bout. Since then, he has been on the shelf, although his name surfaced in news reports in April 2012, when it was reported that he helped rescue an unconscious man on the tracks of a Tokyo subway station.
Though there have been few reports of any issues that would have kept Yamamoto out of action for so long, he has had injury issues in the past.
From Sept. 2002 until Dec. 2007, Yamamoto won 14 matches in a row. At that time, he was considered one of the best lower-weight fighters in the world; since then he's just 1-5.
Menjivar will be attempting to rebound from a February submission loss at the hands of Urijah Faber. Since moving to the UFC from WEC, Menjivar is 4-2.