But even if they draft a receiver with the 16th pick in Thursday's NFL draft, they're not expecting that player to fill the shoes of Johnson, a seven-time Pro Bowler and face of the franchise who was released in March and signed with Indianapolis.
They've already been grooming a No. 1 receiver in DeAndre Hopkins, the 27th pick in the 2013 draft.
Hopkins started moving into the role of top receiver last season when he had a career-high 1,210 yards and six touchdowns to Johnson's 936 yards and three scores.
Hopkins was close to Johnson, who left Houston with 13,597 yards receiving, and declined to comment specifically on his departure. But he did say he's looking forward to helping any receiver they might draft and veteran free agents Nate Washington and Cecil Shorts III.
''When they came in here, I told those guys: `(Ask me) anything you need to know, just about the stadium or where to eat and any little thing,''' Hopkins said.
''I told those guys they could come to me. Coaches are going to help them transition into this offense, but a lot of wide receivers in there look up to me because we don't have 80 (Johnson) here anymore.''
The Texans are in a much different position this season than a year ago when they had the top pick after a 2-14 season and added outside linebacker Jadeveon Clowney.
On Thursday, Louisville receiver DeVante Parker or Southern Cal receiver Nelson Agholor might be available with the 16th pick. Parker finished with 43 receptions for 855 yards and five touchdowns in 2014 despite missing seven games with a foot injury. The speedy Agholor, who is also a punt returner, ran a 4.42 at the combine after leading the Trojans with 104 catches for 1,313 yards and 12 touchdowns as a junior.
Some things to know about the Texans in advance of this week's draft.
NEVER SATISFIED: J.J. Watt is the undisputed face of this team with Johnson gone. The defensive end, who signed a $100 million contract extension before the season, had 78 tackles, 20 1/2 sacks and scored five touchdowns to win Defensive Player of the Year for the second time in his short career. He was a big reason why the Texans improved seven games last season to finish 9-7. But after missing the postseason for the second straight season, Watt is looking for more in 2015.
''A lot of people can say last year was a great year and everything and that's fine,'' Watt said. ''But we're constantly looking to improve. We're never satisfied ... we have big goals.''
CLOWNEY'S HEALTH: The jury's still out on whether Houston's 2014 draft was a success with Clowney missing a majority of the season with injuries. The former South Carolina standout had a rough rookie season from almost the moment he was drafted. He missed the start of training camp after sports hernia surgery and suffered a concussion late in camp. He injured his right knee in his first NFL game and had arthroscopic surgery. Clowney returned for three games, but never returned to form and eventually had season-ending microfracture surgery in December. His recovery is going well and the Texans hope he'll be ready for Week 1. But they might draft an outside linebacker in case he isn't.
QUARTERBACK BATTLE: The Texans were forced to use four different quarterbacks last season because of injuries. But they probably won't draft a quarterback this season after re-signing Ryan Mallett and signing free agent Brian Hoyer in the offseason. Mallett and Hoyer are expected to compete for the starting job.
RUNNING BACK DEPTH: The Texans return Arian Foster, but could draft a running back with Foster dealing with injuries in the past couple of seasons and turning 29 this summer. He was sixth in the NFL with 1,246 yards rushing in 2014 despite missing three games with hamstring injuries. That was a year after back surgery kept him sidelined for eight games.
DEFENSIVE ANCHOR: Houston likely won't be looking for nose tackles in the draft after picking up veteran Vince Wilfork in free agency. Wilfork spent his entire 11-year career with the Patriots, where he piled up 516 tackles. He hopes to blend in seamlessly to a defense featuring Watt and Clowney, and Watt is excited about playing with the big fella.
''I'm looking forward to playing on the line with him because he is very good at what he does and he commands respect from every team,'' Watt said.
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