Houston, TX (SportsNetwork.com) - The Houston Texans announced Monday that the team has signed outside linebacker Whitney Mercilus to a contract extension.

Financial terms of the deal were not disclosed, though NFL.com reported it to be a four-year pact worth $26 million with $10.5 million guaranteed.

The Texans had until midnight Tuesday to decide whether or not to exercise a $7.75 million fifth-year option on Mercilus' rookie contract, which would have expired at the end of the 2015 season had the option not been picked up.

Mercilus, Houston's first-round pick (26th overall) of the 2012 draft, has recorded 18 sacks while starting 33-of-47 games during his first three NFL seasons. The 24-year-old had five sacks along with two forced fumbles and 50 tackles in 13 games in 2014.