The Texans have reached an agreement on a two-year extension with Greg Mancz, according to Mark Berman of FOX 26 (on Twitter). The new deal will keep the offensive lineman under contract through the 2020 season. 
Mancz, a center/guard, was retained for 2018 via the original round tender. After earning $1.907MM in 2018, the new portion of his deal will kick in. Still relatively young at 26, Mancz will be eligible for unrestricted free agency just before his 29th birthday.
The Toledo product has appeared in 29 games for the Texans over the last three years, including 23 starts. Last year, Pro Football Focus ranked Mancz as a top 60 guard in the NFL.