Today those two men took part in their weigh in.
On the scales the champion was 105lbs, bang on the divisional limit. The weight was the same as as he was when he fought Jeffrey Galero in his previous world title bout, back in February.
Tomogdan on the other hand was well inside the limit at 104.5lbs, which is around the same weight he's been in recent bouts.
Whilst Wanheng was the heavier man he was also the shorter man. The champion was measured at 158cm whilst Tomogdan was 165cm. That sort of height difference isn't expected to give Tomogdan much of an advantage given that Wanheng's style is based on bring pressure and grinding his opponents.
For fans interested in watching this one it will be aired on Thai Channel 7 with the broadcast set to begin at 13:58 local time and will run to 16:58.
Wanheng Menayothin takes on Jerry Tomogdan in second world title defense
(Image courtesy of http://www.dailynews.co.th)