The Filipino, fighting in his 41st pro bout, was in dominant form as former unified minimumweight title holder Rodriguez struggled to break through in what was his first world championship bout at 108lbs.
After twelve rounds two judges card 119-109 and 118-110 to Nietes, which seemed correct, although a third judges score of 115-113 didn’t tell the whole story in the fight.
With the win, 33 year-old Nietes improves to 36-1-4 and may now be ready for a further move up in weight, whilst Rodriguez drops to 17-3-1 and is yet to prove himself at the higher limit.
In chief support, featherweight Mark Magsayo made it eleven straight wins as pro by stopping Rafael Reyes in five rounds. The 20 year-old from Tacloban City claimed the IBF Youth belt in the process as Reyes dropped a fifth loss from his 21 contests.
Elsewhere in Madgeburg, Germany, Ruslan Chagaev blasted out Francesco Pianeta in just one round to confirm that the Italian is anything but world title worthy for a second time.