UFC 31 will showcase Ilia Topuria facing off against Charles Oliveira for the vacant UFC lightweight title on Saturday. Here is what to know.

Although Topuria has fought at lightweight in the past, this move up seemingly is a full commitment, and the differences in his frame could be spotted when he stepped on the scale at 155 pounds. There was a brief moment of confusion when the commission representative announced Topuria at 155.

The vacant UFC lightweight championship is up for grabs at UFC 317, with Ilia Topuria vs. Charles Oliveira, with the flyweight title on the line in the co-main.