In the 11th week of the NFL season, there remains little clarity or consistency on pass interference calls and challenges, with a play in the Houston Texans-Baltimore Ravens game the latest instance.

The play unfolded in the first quarter as Texans wide receiver DeAndre Hopkins broke for the end zone wearing Marlon Humphrey like a mink stole well before Deshaun Watson's pass arrived. And yet ... the yellow flags remained firmly planted in officials' pockets. When Bill O'Brien challenged the play, the officials in New York did not deem the no-call worthy of a reversal that would have given the Texans the ball at the 1-yard line.

"I have no idea what pass interference is anymore," Texans Coach Bill O'Brien said at his postgame news conference. "No idea."

"We had another example in the Houston-Baltimore game of the NFL office not overturning a terrible non call on Pass Interference," former coach and NBC analyst Tony Dungy tweeted. "Houston should have had the ball at the 1 yard line. This is getting ridiculous."

Never mind how the call was made on the field; why was it not changed by the officials in New York? That's a question that has been asked several times this season, the first in which pass interference was made reviewable.

Coaches were griping about it right from the start, but, as of mid-October, officials believe the system was working reasonably well, given the limitations of making judgment calls subject to replay scrutiny. They looked to coaches, who were advocates for the replay change, to adjust to rulings being made in New York by Al Riveron, the NFL's senior vice president of officiating.

In a tweet after the game, Hopkins appeared to suggest that Riveron be relieved of his duties.

"As a leader in the NFL, we need someone new in New York deciding calls," the three-time Pro Bowler wrote.

"Everyone saw it," Houston quarterback Deshaun Watson said after the loss. "The guy wrapped him around. But they didn't make that call. You've got to live with it. You can't really dwell on it. [But] it definitely could have been a changing point of the game, a momentum switch. But it's just one of those calls that it didn't go our way and you've got to continue to push forward."

Under the new rule, pass interference calls and no-calls are subject to review by instant replay and can be overturned, with the reviews falling under the coaches' challenge system in the first 28 minutes of each half. In the final two minutes of each half, reviews must be initiated by the replay official in the press boxes at NFL stadiums.

For whatever reason, corrections are rare. ESPN's Kevin Seifert said coaches should stop challenging PI calls and no-calls. "Coaches have now lost 32 of their last 33 pass interference challenges, dating back to the start of Week 4," he wrote. "That's a three-percent success rate. Since Week 3, they are 2-for-41 (4.9 percent). In an age when teams have access to all kinds of analytic probabilities, their coaches should now realize the chances of getting an overturn on pass interference — no matter the severity of the contact — are slim."