Judges Cathy Leonard (USA), Gary Ritter (USA) and Juan Carlos Pelayo (Mexico) all scored it 117-107 in favour of the champion. The Referee was Ian John-Lewis (UK).
Southpaw Yamanaka 25-0-2; 17 floored Solis 23-4-1; 10, a former WBA super flyweight champion midway through the second round but then the compliment wax returned twice in the third round. He then came back to dominate the fight against the Venezuelan challenger.
The champion scored another knockdown with an overhand right in the ninth round and easily won rounds ten, 11 and 12.
Mexican southpaw Ganigan Lopez (27-6, 17 KOs), captured the WBC Light flyweight belt when he scored an upset majority decision over champion Yu Kimura (18-3-1, 3 KOs), in twelve rounds on Friday in Kyoto, Japan.
Lopez maintained the initiative all the way. Cathy Leonard and Gary Ritter (both of US) tallied 119-109 and 118-110 respectively, both in favor of the 34-year-old Mexican, but Juan Carlos Pelayo (Mexico) saw it 114-114. The Referee was Vic Drakulich (US).