Jadeveon Clowney. Later in the game, Mercilus recorded his first sack of the season on Cody Kessler during the 20–7 win. In week 12 against the Tennessee Titans, Mercilus recorded a season high 5 tackles and sacked Marcus Mariota 1.5 times during the 34–17 win. After missing the majority of the previous season due to injury, Mercilus finished the 2018 season with 39 tackles, four sacks, and two forced fumbles in all 16 games played. In the Wild Card Round of the playoffs against the Indianapolis Colts, Mercilus recorded one tackle in the 21–7 loss. 2019 season In the season-opener against the New Orleans Saints, Mercilus sacked and intercepted Drew Brees in the narrow 30–28 road loss. During Week 2 against the Jacksonville Jaguars, Mercilus sacked Gardner Minshew twice and recorded two forced fumbles as the Texans narrowly won 13–12, earning him AFC Defensive Player of the Week. During Week 3 against the Los Angeles Chargers, Mercilus forced Philip Rivers to fumble the football once as the Texans won on the road by a score of 27–20. During Week 7 against the Indianapolis Colts, he recovered a fumble by quarterback Jacoby Brissett in the 30–23 road loss. During Week 15 against the Tennessee Titans, Mercilus intercepted a pass thrown by Ryan Tannehill off a deflection by Justin Reid and returned it for 86 yards during a 24–21 victory. In the next game against the Tampa Bay Buccaneers, he sacked Jameis Winston twice during the 23–20 road victory. On December 28, 2019, the Texans signed Mercilus to a four-year, $53.5 million contract extension with $28.5 million guaranteed. In the AFC wild card game against the Buffalo Bills, he recorded a strip sack on quarterback Josh Allen which was recovered by teammate Jacob Martin during the 22–19 overtime win. 2020 season In Week 4 against the Minnesota Vikings, Mercilus recorded his first two sacks of the season on Kirk Cousins during the 31–23 loss. In Week 5 against the Jacksonville Jaguars, Mercilus recorded a sack and recovered a lost fumble during the 30–14 win. He was placed on the reserve/COVID-19 list by the team on November 5, and activated five days later. He was placed back on the COVID-19 list on December 25, 2020, and activated on January 13, 2021. 2021 season On October 19, 2021, Mercilus was released by the Texans after 10 seasons. Green Bay Packers On October 21, 2021,