[1] After winning 6 consecutive matches, he fought Ruangroj Kiatkriangkrai for the Thai light flyweight championship where he won by unanimous decision on September 28, 1992.

Like his previous attempt for a world crown, Sor Vorapin lost the match in a similar fashion.

Following some wins in seven ordinary matches, Sor Vorapin defended his title by outpointing Mauricio Martinez on August 5, 2005.

In the aftermath of the fight, Vorapin was defeated by an 8th round stoppage from Peñalosa on April 6, 2008 in the event "Invasion: Philippines vs.

[2] On September 14, 2008, Filipino boxer Michael Domingo scored a 9th-round technical knockout victory over Ratanachai Sor Vorapin at the New Cebu Coliseum to retain the regional World Boxing Organization Oriental bantamweight title.