The Texans will play 17 games, as will the rest of the league's teams, for the first time. That means facing 14 teams, instead of 13, and that means facing 14, perhaps more, quarterbacks in 2021. So, how does that compare to last year? Well, let's take a look.
AFC South
Tennessee
2020 starter - Ryan Tannehill (2x)
2021 presumed starter - Tannehill
Tannehill is the only returning quarterback in the division that the Texans faced twice in 2020 and he led the Titans to two nail-biting wins over the Texans 43-37 and 41-38 in 2020.
Indianapolis
2020 starter - Philip Rivers (2x)
2021 presumed starter - Carson Wentz
Rivers drove the Colts offensive truck as well as it could've been done in 2020, but he retired. As such, the Colts traded for Carson Wentz, who had a down 2020 season in Philadelphia.
Jacksonville
2020 starters - Gardner Minshew II, Jake Luton
2021 presumed starter - Trevor Lawrence
Jacksonville has waited decades to have a face of the franchise quarterback and it now has one in Lawrence. Unfortunately, the Texans will now face the 2021 number one overall pick twice a year until eternity.
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Quarterbacks the Texans will face again in 2021:
New England - Cam Newton (potentially)
Cam had one of his best passing games in a loss to the Texans in 2020. He was re-signed in New England but the Patriots also drafted Mac Jones in the first round of 2021.
Los Angeles Rams - Matt Stafford
The Texans faced Stafford as a member of the Detroit Lions but the longtime Detroit star was traded to the Rams in the offseason. The Texans have beaten a Stafford-led squad in 2012, 2016 and 2020 and the Rams come to NRG in 2021.
Cleveland - Baker Mayfield
The Texans are 1-1 against Mayfield in his three year career, unfortunately losing to the Browns in the wild November hail storm in Cleveland in 2020. The Texans return to Cleveland to face Mayfield and the Browns in 2021.
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Quarterbacks outside the AFC South the Texans won't face in the 2021 regular season that they faced in 2020:
Patrick Mahomes, Chiefs
Lamar Jackson, Ravens
Aaron Rodgers, Packers
Ben Roethlisberger, Steelers
Kirk Cousins, Vikings
Mitchell Trubisky, Bears
Brandon Allen, Bengals
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Veteran quarterbacks the Texans have faced in prior years:
Sam Darnold, Panthers (faced him as a member of the Jets in 2018)
Jimmy Garoppolo, 49ers (faced him in 2017)
Josh Allen, Bills (faced him in 2018 and in 2019 playoffs)
Russell Wilson, Seahawks (faced him in 2013 and 2017)
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Veteran quarterbacks the Texans will face for the first time in 2021:
Tua Tagovailoa, Dolphins
Justin Herbert, Chargers
Kyler Murray, Cardinals
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Rookie quarterbacks the Texans will face in 2021:
Trevor Lawrence, Jaguars
Zach Wilson, Jets
(maybe) Mac Jones, Patriots
(maybe) Trey Lance, 49ers
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2020 v. 2021:
Super Bowl winning quarterbacks the Texans faced in 2020 - Mahomes, Rodgers, Roethlisberger (3)
Super Bowl winning quarterbacks they're scheduled to face in 2021 - R. Wilson (1)
Rookies the Texans faced in 2020 - Luton (1)
Rookies the Texans are scheduled to face in 2021 - Lawrence, Z. Wilson (2) - possibility of two more.
League MVP quarterbacks the Texans faced in 2020 - Mahomes, Lamar, Rodgers and Newton (4)
League MVP quarterbacks they're scheduled to face in 2021 - Newton (1)
Pro Bowl quarterbacks the Texans faced in 2020 - Tannehill, Rivers, Newton, Stafford, Mahomes, Jackson, Rodgers, Roethlisberger, Cousins, Trubisky (10)
Pro Bowl quarterbacks the Texans are scheduled to face in 2021 - Tannehill, Wentz, Newton, Stafford, Murray, J. Allen, R. Wilson (6)
Former #1 overall pick quarterbacks the Texans faced in 2020 - Newton, Stafford, Mayfield (3)
Former #1 overall pick quarterbacks the Texans scheduled to face in 2021 - Newton, Stafford, Mayfield, Murray and Lawrence (5)
1st round quarterbacks the Texans faced in 2020 - Tannehill, Rivers, Mahomes, Rodgers, Jackson, Roethlisberger, Newton, Stafford, Mayfield, Trubisky (10)
1st round quarterback the Texans are scheduled to face in 2021 - Tannehill, Wentz, Newton, Stafford, Mayfield, Tua, Murray, J. Allen, Lawrence, Z. Wilson, Herbert, Darnold (12). Only two non-1st round quarterbacks are scheduled to face the Texans in 2021. One is Russell Wilson - the only quarterback on the schedule with a Super Bowl ring and Jimmy Garoppolo who led the 49ers to the Super Bowl in 2019. If Trey Lance somehow supplants Garoppolo in San Francisco, the Texans will presumably face 13 former first round picks and just one non-first round pick - Russell Wilson.