The move was earlier reported Thursday by BuckeyeGrove.com and later confirmed by Vrabel on Twitter.
I am thankful for everyone assoc with TOSU for 3 great years and my family and I are excited to join the Houston Texans as the LB coach.
— Mike Vrabel (@CoachVrabel50) January 9, 2014
Vrabel, who will replace Reggie Herring in Houston, spent three years as a Buckeyes assistant, coaching the linebackers in 2011 and overseeing the defensive line the past two seasons. Also one of coach Urban Meyer's best recruiters, Vrabel was named the ESPN.com national recruiter of the year in 2012.
Ohio State was Vrabel's first college coaching job. He is best known for his time as a linebacker with the New England Patriots, with whom he won three Super Bowls. Texans coach Bill O'Brien was an assistant with the Patriots during Vrabel's playing days and competed against Vrabel's Buckeyes as Penn State's coach the past two years.
O'Brien fired Texans defensive coordinator Wade Phillips and most of the team's position coaches on Saturday, one day after being officially introduced as Houston's head coach. Defensive line coach Bill Kollar was the only defensive position coach O'Brien retained.
The Texans also will hire several coaches who worked under O'Brien at Penn State, sources said. Former Penn State strength and conditioning coach Craig Fitzgerald and his staff, defensive coordinator John Butler, safeties coach Anthony Midget, running backs coach Charles London and receivers coach Stan Hixon all resigned from Penn State this week and will join the Texans.
O'Brien interviewed Romeo Crennel on Wednesday for the position of defensive coordinator. Crennel has one more year left on his contract with the Kansas City Chiefs, who fired him after the 2012 season, and will make $3.5 million this year whether or not he works.
Vrabel is the second defensive assistant to leave the Buckeyes this offseason. Co-defensive coordinator Everett Withers left last month to take the head coaching job at James Madison.