Photo: Brett Coomer, Houston Chronicle / Staff Photographer

EAST RUTHERFORD, N.J. — In some ways, it is a misleading statistic.

It also captures the state of the 2018 Texans.

The last time Deshaun Watson threw for at least 300 yards: Week 5 against the Dallas Cowboys at NRG Stadium.

Watson was blasted in that nationally televised in-state showdown, sacrificing his body multiple times for a 19-16 overtime victory that helped ignite a franchise-record nine-game win streak.

Since Oct. 7, the Texans’ passing game — for better and worse — hasn’t been the same. As Bill O’Brien’s team enters a final three-game window that should lead toward an AFC South title and home playoff contest, one of the key questions that remains is whether the Texans can start airing it out again in time for the postseason.

Just don’t mention the old-fashioned 300-yard marker to a coach solely focused on trying to answer a disappointing home defeat to Indianapolis with a road victory Saturday against the annually disappointing New York Jets.

“I feel fine where the passing game’s at,” O’Brien said this week as his 9-4 team prepared for a 4-9 squad directed by rookie quarterback Sam Darnold. “I’m not worried about 300-yard passing games. I’m not worried about 150-yard rushing games. I’m just — and I think we all are — worried about winning. Whatever it takes to win. Not really into the stats. Never really cared about stats.”

Watson’s numbers have increasingly become encouraging, intriguing and somewhat contradictory in 2018. The highly confident and charismatic 23-year-old is clearly the Texans’ long-elusive answer at QB. As one of the driving forces who turned 0-3 into 9-3, Watson has completed 66.9 percent of his passes — a 5 percent uptick from his rookie campaign — for 3,298 yards, 22 touchdowns, nine interceptions and a 100.9 rating.

Yet Andrew Luck (399 yards) was the best field general inside NRG during the Colts’ victory Sunday. Rookie Baker Mayfield (397 yards) outdueled Watson in Week 13 on the Texans’ home field. And the No. 12 overall pick of the 2017 draft is averaging only 224.4 passing yards in his last five games.

The scaled-back passing was intentional as Watson recovered from multiple injuries at once. The Texans protected their franchise centerpiece by becoming run-first and limiting the opportunities opponents had to hammer the 6-2, 220-pound QB.

Add in the midseason loss of primary deep threat Will Fuller and an unpredictable offensive line that has allowed the second-most sacks (46) in the NFL, and the Texans stayed alive, then surged forward in 2018 by going old school: run, pass, run.

But this season is mostly being defined by constant passing and nonstop offense. The league’s elite teams (Kansas City, New Orleans, Los Angeles Rams and Chargers) are led by explosive QBs. The Saints’ Drew Brees tops the NFL with a surreal 75.7 completion percentage. The Chiefs’ Patrick Mahomes, drafted two slots ahead of Watson, has thrown for a league-high 4,543 yards and 45 TDs. The Chargers’ Philip Rivers, 37, silenced Mahomes and the Chiefs at Kansas City in a thrilling Thursday night comeback.

Watson ranks 18th in yards per game (254), 14th in completion percentage and 13th in touchdowns.

Average, not exceptional.

Yet one of his most promising stats also highlights the Texans’ limited passing attack. Watson is sixth in the league in yards per attempt (8.2). Four of the five arms ahead of him: Mahomes, Rivers, the Rams’ Jared Goff and Brees.

Why not throw more if Watson is so efficient at it?

He’s tossed 13 TDs since Week 6 yet has handed out only two picks.

More importantly: Can the Texans make an impact in the playoffs if they keep holding back their best offensive asset?

The only thing getting in Watson’s way is unreliable pass protection. And that’s the organization’s fault, not his.

“I think we have to do some things better relative to route running, reads, protection, design of the play,” said O’Brien, when asked about the state of the Texans’ passing game.

The one stat the coach truly believes in: positive turnovers.

Watson averaged 361.2 passing yards during Weeks 2-5. But he also threw at least one pick in his initial six games this season, with several killing potential scoring drives

“The biggest stat that I really care about is the takeaway-giveaway stat. I think that’s one of the biggest stats,” O’Brien said. “We’re tied for fourth in the league (plus-nine) right now. I think we’ve got to try to keep that going. We’ve done a good job of taking care of the ball. We’ve got to take the ball away even better than we do. But that’s really the only stat that I’m totally concerned about. The biggest stat is winning.”

Watson’s efficiency has increased as his attempts have decreased. Sunday’s loss marked the first time since Week 5 that he attempted more than 32 passes. The 38 throws came in defeat, though, with the Texans playing from behind and trying to catch up to Luck.

Against the Colts, Watson was sacked five times for 41 yards. He also held on to the ball too long, leading to several negative-yardage takedowns, and misfired on a couple of potential scores.

“I think the biggest thing is really the deep shots down the field, capitalizing on those more,” Watson said. “Also not taking too many sacks and really just taking what the defense is giving me. Really, the biggest thing is whenever we throw the ball downfield, whenever those opportunities come, just capitalize on those.”

He has the arm, accuracy and field vision required. He can burn the opposition with his legs and rushed for 135 yards during the last three games. It’s also not a coincidence the Texans ran off nine consecutive wins after the team’s offensive leader began playing with a cracked rib and partially collapsed lung.

But Watson knows he must be sharper and more dangerous as January approaches.

It’s on the Texans to get more out of their franchise QB.

brian.smith@chron.com

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