When the Houston Texans take to the field inside NRG Stadium against the Jacksonville Jaguars (1-3) on Sunday, things will look drastically different on the sideline.

For the first time since joining the franchise as a defensive coordinator in 2014, Romeo Crennel, 73, will serve as head coach of the Texans following the recent jettisoning of Bill O'Brien on Monday. The news of O'Brien's firing came a day after the Texans fell 31-23 at the hands of the Minnesota Vikings — dropping the team to an 0-4 start to the season.

An hour after the news broke, O'Brien took to the podium for his final press conference dressed in a solid gray polo-shirt instead of his usual NFL coaching gear with his signature white hat sporting the Texans' logo in the middle.

In his opening statement via Zoom, O'Brien expressed that he does not regret anything during his six-year tenure with the organization, but acknowledged that he did not do enough as head coach to put the Texans in a position to win a championship title.

In his first year at the helm in 2014, O'Brien helped the Texans improve by seven wins from the previous season (9-7). Six years later, he became the winningest coach in franchise history in terms of winning percentage (.520) and led the Texans to four AFC South titles.

Despite the disappointments in the playoffs, in a perfect world, the on-field success Houston endured with O'Brien should have kept him around until the conclusion of his contract in 2022.

However, O'Brien mentioned not doing enough for the organization on four separate occasions — which demonstrated his only regret as head coach. But in reality, as general manager, O'Brien did too much to this organization that it forced Texans Chairman and Chief Executive Officer Cal McNair to throw his hands in the air and say enough.

"We won four division championships in six years, so we did a lot of good things here, but we didn't do enough," O'Brien said. "We didn't bring a Super Bowl to Houston, which I believe eventually someone will. I think this is a championship team that needs to get things turned around right now, but I believe in this team."

Each time the Texans step onto the field this season, it is a constant reminder of how O'Brien the GM has throttled Houston's talents in a year. And Houston's on-field problems exceed beyond the departure of Jadeveon Clowney and DeAndre Hopkins.

The Texans' run game has become appalling in 2020. Houston went from having a top-10 running game in 2019, averaging 125.6 yards on the ground to dead last this season, recording an average of 73.5 yards through the first four games. The result of the Texans' digression stems from O'Brien's decision to let Carlos Hyde walk in free agency.

Albeit he is far from his counterparts in Dalvin Cook and Derrick Henry, Hyde gave the Texans a substantial amount of production coming out of the backfield during his lone season in Houston.

In 2019, he rushed for over 1,000 yards (1,070) and racked up six touchdowns on 245 carries. In his first four games with the team, Hyde had already established himself as a quality running back with 250 yards totaled on the ground, averaging 4.9 yards per attempt — filling in the void left by an injured Lamar Miller.

In comparison to David Johnson, the former All-Pro tailback (2016) has looked futile through his first four games as Hyde's replacement.

Johnson had a solid debut during Houston's season opener against the Chiefs. He recorded 77 yards (7.0 AVG.) on 11 carries, and scored the Texans' first touchdown of the season. Since his performance inside Arrowhead Stadium, D.J. has regressed to a total of 120 rushing yards, averaging 3.0 yards per attempt over the last three games. He added one additional touchdown to his season total, but it came on a two-yard rush — nothing to boast about.

Not retaining Hyde after a career season has caused significant ramifications for the Texans on offense, but O'Brien's moves as GM on the defensive side of the ball is abominable.

"I think at the end of the day I tried to do what was best for the organization — what was asked of me," O'Brien said. "I really did. Obviously, we made mistakes. I don't think anybody's perfect, but we worked very hard to field a competitive team."

Last season, the Texans' defense did regress from the previous year, but they were still respectable at the very least. Houston had their share of struggles at times, but it was enough to create disruption and force turnovers.

In 2019, the Texans placed in the 15th percentile in turnovers with 22 (12 INT, 10 FUM) — five came within the first four games of the season. Fast-forward a year later, Houston's lack of talent has yet to create a single turnover entering Week 5. But the Texans' most significant issue in their defense has been their inability to stop the run.

The Texans allowed their opponents to rush for an average of 121.1 yards per game last season. Although not ideal, it is an exceptional feat for a team that has allowed a league-worst 181.8 yards in rushing thus far in 2020. The results, O'Brien the GM departing from Jahleel Addae, Tashaun Gipson, Johnathan Joseph and D.J. Reader in one offseason.

A year ago — months before O'Brien took the position as GM — the future seemed bright in Houston. They had two generational talents on both sides of the ball, which led many to believe that the Texans would represent the AFC in Super Bowl LIV against the New Orleans Saints. Today, the Texans' future is in a snafu state because of the outrageous decisions made by O'Brien, the general manager.

During his exit, Bill O'Brien showed some remorse for not doing enough as head coach of the Texans. Although true, his decisions as a general manager is what ultimately led to his demise in Houston. As general manager, Bill O'Brien did entirely too much.

"I'm just sorry we couldn't get it done this year early on here. But I wish them the best. This is a good football team. Romeo [Crennel] stepped in. He's an awesome coach, and he'll do a great job. This has given me a great perspective, and I will take this experience with me to my next opportunity." — O'Brien.