Machorro participated in the team's rookie minicamp on a tryout basis.
Listed at 6-foot-6 and 302 pounds, Machorro was named the Lone Star Conference Offensive Lineman of the Year in 2017 while playing for Texas AM-Commerce.
The Colts waived center Anthony Fabiano on Monday.
Fabiano played in nine career games with the Colts and Cleveland Browns. He spent time on both the active roster and practice squad in 2017.