Standing next to star quarterback Deshaun Watson on the Texans’ practice field, Tim Kelly has a different vantage point and vastly expanded responsibilities.

As a rookie offensive coordinator, Kelly has been preparing for this role for a long time.

Promoted from tight ends coach this offseason, the 32-year-old Chicago Heights, Ill., native is tasked with making sure the entire offense runs smoothly.

That involves everything from making sure the game plan capitalizes fully on Watson’s dual-threat capabilities to managing a talented receiving corps headlined by All-Pro DeAndre Hopkins to significantly upgrading the pass protection.

Although Kelly will help build game plans and work in tandem with Bill O’Brien on strategy, the Texans’ head coach remains the play-caller.

When O’Brien told the former Penn State graduate assistant he was being promoted to offensive coordinator, it was a huge moment for Kelly after years of working behind the scenes.

“It was great,” Kelly said Tuesday following an organized team activity. “I worked really hard, put in a lot of hours. Now is the hard part. Don’t mess it up is the philosophy right now. It was a great honor.”

Kelly had risen in the coaching ranks under O’Brien from offensive quality control to tight ends. He hasn’t been an offensive coordinator before but is regarded highly for his coaching acumen, people skills and adaptability.

“I think being able to go out there and score a lot of points is obviously something all offensive coordinators want to be responsible for,” Kelly said. “Having a sound, smart football team in the image that coach O'Brien wants it, making sure everyone is prepared when we step on the field.”

It’s unclear when or if Kelly will incorporate play-calling duties into his job. For now, it’s O’Brien’s show to run, and Kelly will operate in a complementary role.

“Right now, I'm just really worrying about making sure that the offense is ready for OTAs when we take the field,” Kelly said. “So I guess we will cross that bridge at a later date.”

Developing into the ultimate arbiter on what plays the offense runs takes a lot of time. O’Brien is expected to groom Kelly for that kind of role in the future.

“Every play-caller starts somewhere, so where do you start?” O’Brien said. “Where does the process start as a play-caller? It starts with obviously having a great understanding of your system, having a great understanding of defense, which Timmy does. And then it starts with how much scripting do you want to give them. Will he call the plays in practice? Who will translate the play from the script, or even off the script, to the quarterback in practice?

“There’s a lot of ways you can train a play-caller. You have to get a feel for it. You have to get a feel for your team. You have to understand how the game’s being played, how you’re being played defensively and things like that. Those are all things that we will work through.”

O’Brien likes Kelly’s knowledge of the offense, prodigious work ethic and creativity.

“If you look at a guy like Tim Kelly, a very bright guy, a very young coach in the business relative to years of experience, but he’s really risen the ladder because of his work ethic and his intelligence, and he’s coached on both sides of the ball,” O’Brien said. “He was with me at Penn State, came with me to Houston, has done a fantastic job in every role that I’ve asked him to take on, and he earned the opportunity.

“He knows the system. He knows where the system needs to be improved; he knows how it can be tweaked. He knows the things that we have to keep doing that we did well last year.”

Kelly drew praise all season from O’Brien for his work with the tight ends, bringing along Jordan Thomas and Jordan Akins as rookies last year.

Now, Kelly has to concern himself with the bigger picture. Expanding his scope from the tight end meeting room to planning practices and helping to evaluate personnel groupings and the finer points of the offense represents a big change for Kelly.

He has O’Brien and veteran quarterbacks coach Carl Smith to lean on, though.

“Scripting — taking care of, basically, the general organization of practice on the offensive side of the ball — that’s more of the stuff that I guess I’m focused on now as opposed to just handling the tight end room,” Kelly said. “So I would say right now that’s the biggest adjustment that I’ve had to make.”

Working closely with Watson, Kelly wants to make sure the Pro Bowl alternate has sufficient time to operate after he was sacked an NFL-high 62 times last season.

As dangerous as Watson is when he’s improvising, Kelly wants to make sure that part of his game remains a hallmark of the offense.

“That’s part of what makes him so great,” Kelly said. “It’s about making sure he understands the offense and taking calculated risks.”

Kelly is already building a strong rapport with the Texans’ top offensive players, including Watson and Hopkins.

“I'm very excited for Tim with the opportunity he has,” Watson said. “He’s really embracing the whole OC gig, and he’s doing a great job.”

Said Hopkins: “He’s a great guy, great coach. So I’m looking forward to working with him. It’s good.”

A former defensive tackle and team captain at Eastern Illinois, Kelly started 48 career games and was a two-time academic all-district selection.

He’s been preparing for this higher-profile assignment during his previous coaching jobs at Illinois Wesleyan, Minnesota State Moorhead, Ball State and Penn State.

Since joining the Texans, he’s been an offensive quality control coach and an assistant offensive line coach before taking over the tight ends two years ago.

At each stage in his development as a coach, Kelly has been successful. Being an offensive coordinator represents his greatest challenge yet.

“Win. That’s the most important thing — and making sure we do a great job of getting our guys ready,” Kelly said. “I don’t think there’s any definitive style. It’s more so just whatever we have to do to win that game.”

aaron.wilson@chron.com

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