Grading Texans in free agency: Defense gets lift by adding Tyrann Mathieu

A breakdown of the initial wave of free agency for the Houston Texans:

Overall grade: B. The Texans filled some holes on both offense and defense but did not add a left tackle to protect quarterback Deshaun Watson, who is coming off ACL surgery. Houston still has time to add talent there, but without a draft pick in the first two rounds, the options are pretty limited.

Most significant signing: Tyrann Mathieu. Houston was missing a playmaker in the secondary last season but hope to have found one in the former Arizona Cardinals safety. Although Mathieu has finished three of his five NFL seasons on injured reserve, he played 16 games in 2017 and led the NFL in total snaps. If J.J. Watt, Jadeveon Clowney and Whitney Mercilus can all stay healthy next season, the addition of Mathieu will further help the Texans regain their status as a top-tier NFL defense.

Most significant loss: None. The Texans didn’t have a big free-agent class and were able to re-sign cornerback Johnathan Joseph. Houston did cut longtime linebacker Brian Cushing, who last year served the second suspension of his career for violating the NFL’s policy on performance-enhancing substances. At Cushing's salary and considering the impressive play of rookie linebackers Zach Cunningham and Dylan Cole, it made no sense to bring Cushing back.

Player they should have signed: Nate Solder. The former New England Patriots left tackle would have come at a high cost -- he signed a four-year, $62 million contract with the New York Giants -- but the Texans had the money. Protecting Watson was a priority for Houston, and they did add three offensive linemen during free agency (guards Zach Fulton and Senio Kelemete and tackle Seantrel Henderson), but Solder would have filled a big need.

What’s next: Finding a veteran running back. The Texans only have two established running backs on their roster: Lamar Miller and D'Onta Foreman. Foreman, a third-round pick in 2017, is recovering from a torn Achilles and is not expected to be ready for the Texans' spring workouts. While he is on pace to return for training camp, Houston needs depth at the position. Alfred Blue is still a free agent and could return as a reserve.

Additions: S Tyrann Mathieu (Cardinals), CB Aaron Colvin (Jaguars), G Zach Fulton (Chiefs), G Senio Kelemete (Saints), T Seantrel Henderson (Bills), CB Johnson Bademosi (Patriots), WR Sammie Coates (Browns), QB Brandon Weeden

Losses: LB Brian Cushing, QB Tom Savage, T Breno Giacomini, S Marcus Gilchrist, QB Josh Johnson, G Xavier Su'a-Filo